- Antimicrobial activity and microbial transformation of ethyl p-methoxycinnamate extracted from Kaempferia Galanga
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Ethyl p-methoxycinnamate (EPMC), a major constituent of the Kaempferia galanga rhizome, was transformed to ethyl p-hydroxycinnamate (EPHC) using Aspergillus niger. The EPHC metabolite was elucidated by NMR spectroscopic technique. Antimicrobial microbial
- Omar, Muhammad Nor,Hasali, Nor Hazwani Mohd,Alfarra, Helmi Yousif,Yarmo, Mohd Ambar,Zuberdi, Ahmad Muzammil
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- Prenylated trans-cinnamic esters and ethers against clinical fusarium spp.: Repositioning of natural compounds in antimicrobial discovery
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Onychomycosis is a common nail infection mainly caused by species belonging to the F. oxysporum, F. solani, and F. fujikuroi species complexes. The aim of this study was to evaluate the in vitro susceptibility of six representative strains of clinically relevant Fusarium spp. toward a set of natural-occurring hydroxycinnamic acids and their derivatives with the purpose to develop naturally occurring products in order to cope with emerging resistance phenomena. By introducing a prenylated chain at one of the hydroxy groups of trans-cinnamic acids 1–3, ten prenylated derivatives (coded 4–13) were preliminarily investigated in solid Fusarium minimal medium (FMM). Minimal inhibitory concentration (MIC) and lethal dose 50 (LD50) values were then determined in liquid FMM for the most active selected antifungal p-coumaric acid 3,3′-dimethyl allyl ester 13, in comparison with the conventional fungicides terbinafine (TRB) and amphotericin B (AmB), through the quantification of the fungal growth. Significant growth inhibition was observed for prenylated derivatives 4–13, evidencing ester 13 as the most active. This compound presented MIC and LD50 values (62–250 μM and 7.8–125 μM, respectively) comparable to those determined for TRB and AmB in the majority of the tested pathogenic strains. The position and size of the prenylated chain and the presence of a free phenol OH group appear crucial for the antifungal activity. This work represents the first report on the activity of prenylated cinnamic esters and ethers against clinical Fusarium spp. and opens new avenues in the development of alternative antifungal compounds based on a drug repositioning strategy.
- Balmas, Virgilio,Carta, Paola,Casalini, Stefano,Chtioui, Wiem,Delogu, Giovanna,Dettori, Maria A.,Fabbri, Davide,Migheli, Quirico,Oufensou, Safa
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- Larvicidal activity and in silico studies of cinnamic acid derivatives against Aedes aegypti (Diptera: Culicidae)
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Cinnamic acid derivatives (CAD's) represent a great alternative in the search for insecticides against Aedes aegypti mosquitoes since they have antimicrobial and insecticide properties. Ae. aegypti is responsible for transmitting Dengue, Chikungunya, and Zika viruses, among other arboviruses associated with morbimortality, especially in developing countries. In view of this, in vitro analyses of n-substituted cinnamic acids and esters were performed upon 4th instar larvae (L4) of Ae. aegypti, as well as, molecular docking studies to propose a potential biological target towards this mosquitoes species. The larvicide assays proved that n-substituted ethyl cinnamates showed a more pronounced activity than their corresponding acids, in which p-chlorocinnamate (3j) presented a LC50 value of 8.3 μg/mL. Thusly, external morphologic alterations (rigid and elongated body, curved bowel, and translucent or darkened anal papillae) of mosquitoes’ group exposed to compound 3j, were observed by microscopy. In addition, an analytical method was developed for the quantification of the most promising analog by using high-performance liquid chromatography with UV detection (HPLC-UV). Molecular docking studies suggested that the larvicide action is associated with inhibition of acetylcholinesterase (AChE) enzyme. Therefore, expanding the larvicidal study with the cinnamic acid derivatives against the vector Ae. aegypti is important for finding search for more effective larvicides and with lower toxicity, since they have already shown good larvicidal properties against Ae. aegypti.
- Bezerra Fran?a, Saraliny,Carine Barros de Lima, Luana,Rychard da Silva Cunha, Cristhyan,Santos Anuncia??o, Daniela,Ferreira da Silva-Júnior, Edeildo,Ester de Sá Barreto Barros, Maria,José da Paz Lima, Dimas
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- Hybrids of 4-hydroxy derivatives of goniothalamin and piplartine bearing a diester or a 1,2,3-triazole linker as antiproliferative agents
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A library of nine hybrids of 4-hydroxygoniothalamin (2), 4-hydroxypiplartine (4), monastrol (5) and oxo-monastrol (6) was prepared via a modular synthetic route with a diester or a 1,2,3-triazole as linkers. The compounds were assayed against a panel of h
- Grigolo, Thiago A.,Braga, Carolyne B.,Ornelas, Catia,Russowsky, Dennis,Ferreira-Silva, Guilherme A.,Ionta, Marisa,Pilli, Ronaldo A.
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supporting information
(2021/09/14)
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- Bimetallic Ni–Pd Synergism—Mixed Metal Catalysis of the Mizoroki-Heck Reaction and the Suzuki–Miyaura Coupling of Aryl Bromides
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Abstract: A combination of Pd and Ni complexes activated aryl bromides for the thermal Mizoroki-Heck reaction and Suzuki coupling giving high yields in short reaction times. A thermal redox mechanism probably occurs whereby Ni complex transfers electron and reduces the Pd (II) to Pd (0) which then takes the reactants through the standard protocol of oxidative-addition, migratory insertion and reductive elimination, typical for the Mizoroki-Heck reaction and the Suzuki coupling. Graphic Abstract: [Figure not available: see fulltext.]
- Kashid, Abhijit A.,Patil, Dharmaraj J.,Mali, Ramling D.,Patil, Vijay P.,Neethu,Meroliya, Heena K.,Waghmode, Shobha A.,Iyer, Suresh
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p. 353 - 358
(2020/08/05)
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- Aryl phenol compound as well as synthesis method and application thereof
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The invention discloses a synthesis method of an aryl phenol compound shown as a formula (3). All systems are carried out in an air or nitrogen atmosphere, and visible light is utilized to excite a photosensitizer for catalyzation. In a reaction solvent, ArNR1R2 as shown in a formula (1) and water as shown in a formula (2) are used as reaction raw materials and react under the auxiliary action of acid to obtain the aryl phenol compound as shown in a formula (3). The ArNR1R2 in the formula (1) can be primary amine and tertiary amine, can also be steroid and amino acid derivatives, and can also be drugs or derivatives of propofol, paracetamol, ibuprofen, oxaprozin, indomethacin and the like. The synthesis method has the advantages of cheap and easily available raw materials, simple reaction operation, mild reaction conditions, high reaction yield and good compatibility of substrate functional groups. The fluid reaction not only can realize amplification of basic chemicals, but also can realize amplification of fine chemicals, such as synthesis of drugs propofol and paracetamol. The invention has wide application prospect and use value.
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Paragraph 0149-0152
(2021/05/12)
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- Ruthenium-catalyzed intramolecular arene C(sp2)-H amidation for synthesis of 3,4-dihydroquinolin-2(1 H)-ones
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We report the [Ru(p-cymene)(l-proline)Cl] ([Ru1])-catalyzed cyclization of 1,4,2-dioxazol-5-ones to form dihydroquinoline-2-ones in excellent yields with excellent regioselectivity via a formal intramolecular arene C(sp2)-H amidation. The reactions of the 2- and 4-substituted aryl dioxazolones proceeds initially through spirolactamization via electrophilic amidation at the arene site, which is para or ortho to the substituent. A Hammett correlation study showed that the spirolactamization is likely to occur by electrophilic nitrenoid attack at the arene, which is characterized by a negative ρ value of -0.73.
- Au, Chi-Ming,Ling, Cho-Hon,Sun, Wenlong,Yu, Wing-Yiu
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supporting information
p. 3310 - 3314
(2021/05/29)
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- Alkyl and aryl derivatives based on p-coumaric acid modification and inhibitory action against leishmania braziliensis and plasmodium falciparum
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In low-income populations, neglected diseases are the principal cause of mortality. Of these, leishmaniasis and malaria, being parasitic, protozoan infections, affect millions of people worldwide and are creating a public health problem. The present work evaluates the leishmanicidal and antiplasmodial action of a series of twelve p-coumaric acid derivatives. Of the tested derivatives, eight presented antiparasitic activities 1-3, 8-12. The hexyl p-coumarate derivative (9) (4.14 ± 0.55 μg/mL; selectivity index (SI) = 2.72) showed the highest leishmanicidal potency against the Leishmania braziliensis amastigote form. The results of the molecular docking study suggest that this compound inhibits aldehyde dehydrogenase (ALDH), mitogen-activated kinase protein (MPK4), and DNA topoisomerase 2 (TOP2), all of which are key enzymes in the development of Leishmania braziliensis. The data indicate that these enzymes interact via Van derWaals bonds, hydrophobic interactions, and hydrogen bonds with phenolic and aliphatic parts of this same compound. Of the other compounds analyzed, methyl p-coumarate (64.59 ± 2.89 μg/mL; IS = 0.1) demonstrated bioactivity against Plasmodium falciparum. The study reveals that esters presenting a p-coumarate substructure are promising for use in synthesis of derivatives with good antiparasitic profiles.
- De Sousa, Dami?o P.,Lopes, Susiany P.,Pérez-Castillo, Yunierkis,Robledo, Sara M.,Yepe, Lina M.
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supporting information
(2020/08/24)
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- Coumaric acid analogues inhibit growth and melanin biosynthesis in Cryptococcus neoformans and potentialize amphotericin B antifungal activity
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Fungal infections are on the rise, since the imunocompromised population is increasing due to AIDS/HIV, organ transplant and chemotherapy. Many environmental and pathogenic fungi are able to accomplish melanin biosynthesis as a virulence factor to promote host invasion. Melanized cells are more resistant to radiation, oxidative and osmotic stresses; also melanin confers an advantage in vivo, since melanized cells are more resistant to phagocytic engulfment and oxidative stress caused by the host defense cells and by some antifungal drugs, such as fluconazole (FCZ) and amphotericin B (AmB). Brown, red or black melanin pigments can be produced by the polyketide pathway (DHN-melanin) or from dihydroxyphenols, such as L-DOPA (L-3,4-dihydroxyphenylalanine) and L-tyrosine by polyphenoloxidases. Among several pathogenic fungi, Cryptococcus neoformans is a melanized yeast that causes pneumonia and meningoencephalitis in immunocompromised patients. The knockout of the laccase genes or other interruptions on melanin biosynthetic pathway generates cryptococcal strains with attenuated virulence in an animal model. In this study 16 analogues of coumaric and cinnamic acid were evaluated as possible tyrosinase inhibitors. We have identified some valuable inhibitors of C. neoformans growth and melanin biosynthesis disruption agents. The results showed that coumaric acid derivatives (1a-c), the ketones (3a-b) and 2-allylphenol (7c) are significant inhibitors of tyrosinase and melanization of the fungus. Two analogues (1b and 3b) were selected as promising antimelanogenic agents to be combined with AmB, showing to promote 16-fold reduction in the AmB fungicidal concentration with no appreciable cytotoxicity to mammalian cells. The data suggest that inhibition of the melanin biosynthesis by these compounds may increase the susceptibility of the cells to the oxidative stress generated by AmB. In summary, our data show that C. neoformans can be a suitable model system to test novel inhibitors that target melanin biosynthesis, and novel compounds for adjunct therapy against C. neoformans were identified.
- Melhem, Marcia S. C.,Oliveira, Lidiane,Pascon, Renata C.,Vallim, Marcelo A.,Varela, Marina Themoteo,dos Santos, Alexandre Paes,Corrêa, Isabela Teresa Santos,Fernandes, Jo?o Paulo S.,Ferrarini, Márcio,Tempone, André Gustavo
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- Coumaric acid derivatives as tyrosinase inhibitors: Efficacy studies through in silico, in vitro and ex vivo approaches
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p-Coumaric acid is a known inhibitor of tyrosinase, an enzyme involved in the initial steps of the melanin synthesis in human and other species. However, its low lipophilicity impairs its penetration through skin and efficacy as antimelanogenic agent indeed. Accordingly, this paper reports the assessment of several coumaric acid derivatives as tyrosinase inhibitors and antimelanogenic agents in in vitro, in silico and ex vivo assays. The compounds were designed with modifications in the aromatic and acid moieties of p-coumaric acid, being the coumarate esters the most promising derivatives. The compounds showed higher tyrosinase inhibitory activity (pIC50 3.7–4.2) than the parent acid, being compounds 1d, 1e and 1f the most potent inhibitors. Docking analysis showed that these esters are competitive inhibitors per se, and act independently of a redox mechanism as suggested by DPPH assays. Moreover, the esters showed efficacy in reducing the melanin deposition in human skin fragments at 0.1% concentration, especially compound 1e. In summary, there is an important equilibria between tyrosinase affinity and lipophilicity that must be considered to get effective antimelanogenic agents with adequate permeability in the skin.
- Fernandes, Jo?o Paulo S.,Ferrarini, Márcio,Mercaldi, Vitória Gallo,Nazato, Lucas Idacir Sbrugnera,Padovani, Giovana,Sufi, Bianca da Silva,Varela, Marina Themoteo
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- Grafting Nature-Inspired and Bio-Based Phenolic Esters onto Cellulose Nanocrystals Gives Biomaterials with Photostable Anti-UV Properties
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New nature-inspired and plant-derived p-hydroxycinnamate esters and p-hydroxycinnamate diesters provide excellent protection against UV radiation when incorporated into a matrix. Herein, an efficient and sustainable pathway is reported to graft these phenolic compounds onto cellulose nanocrystals (CNCs) via click-type copper-catalyzed azide/alkyne cycloaddition (CuAAC) reaction. The successful grafting of the phenolic esters on CNC surface was evidenced by a range of chemical analyses, and the degrees of substitution (DS) of the CNC were found to depend on the structure of the phenolic ester grafted. Moreover, aqueous suspensions of the phenolic ester-grafted CNCs not only strongly absorb in both the UVA and UVB regions, but they also exhibit average to very high photostability. Their wide spectrum UV-absorbing properties and their stability upon exposure to UV are highly influenced by the structure of the phenolic ester, particularly by the extra ester group in p-hydroxycinnamate diesters. These findings demonstrate that cellulose nanocrystals decorated with such plant-derived and nature-inspired phenolic esters are promising sustainable nanomaterials for anti-UV applications.
- Allais, Florent,Browne, Christine,Garnier, Gil,Joram Mendoza, David,Mouterde, Louis M. M.,Simon, George P.,Singh Raghuwanshi, Vikram
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- Structure?Activity Relationships of Cinnamate Ester Analogues as Potent Antiprotozoal Agents
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Protozoal infections are still a global health problem, threatening the lives of millions of people around the world, mainly in impoverished tropical and sub-tropical regions. Thus, in view of the lack of efficient therapies and increasing resistances against existing drugs, this study describes the antiprotozoal potential of synthetic cinnamate ester analogues and their structure-activity relationships. In general, Leishmania donovani and Trypanosoma brucei were quite susceptible to the compounds in a structure-dependent manner. Detailed analysis revealed a key role of the substitution pattern on the aromatic ring and a marked effect of the side chain on the activity against these two parasites. The high antileishmanial potency and remarkable selectivity of the nitro-aromatic derivatives suggested them as promising candidates for further studies. On the other hand, the high in vitro potency of catechol-type compounds against T. brucei could not be extrapolated to an in vivo mouse model.
- Bernal, Freddy A.,Kaiser, Marcel,Wünsch, Bernhard,Schmidt, Thomas J.
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- Discovery of a series of selective and cell permeable beta-secretase (BACE1) inhibitors by fragment linking with the assistance of STD-NMR
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Two β-secreatase (BACE1) inhibitors from natural products (cinnamic acid and flavone) were linked to furnish potent, cell permeable BACE1 inhibitors with noncompetitive mode of inhibition, with the assistance of saturated transfer difference (STD)-NMR technique. Some of these conjugates also exhibited selective BACE1 inhibition over other aspartyl proteases such as BACE-2 and renin, as well as poor cytotoxicity. Taken together, conjugates 4 represent a new series of BACE inhibitors warrants further investigation for their potential in Alzheimier's disease therapy.
- Fang, Wei-Shuo,Sun, De-yang,Yang, Shuang,Cheng, Chen,Moschke, Katrin,Li, Tianqi,Sun, Shanshan,Lichtenthaler, Stefan F.,Huang, Jian,Wang, Yinghong
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supporting information
(2019/09/30)
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- Ipomoeassin F Binds Sec61α to Inhibit Protein Translocation
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Ipomoeassin F is a potent natural cytotoxin that inhibits growth of many tumor cell lines with single-digit nanomolar potency. However, its biological and pharmacological properties have remained largely unexplored. Building upon our earlier achievements
- Zong, Guanghui,Hu, Zhijian,O'Keefe, Sarah,Tranter, Dale,Iannotti, Michael J.,Baron, Ludivine,Hall, Belinda,Corfield, Katherine,Paatero, Anja O.,Henderson, Mark J.,Roboti, Peristera,Zhou, Jianhong,Sun, Xianwei,Govindarajan, Mugunthan,Rohde, Jason M.,Blanchard, Nicolas,Simmonds, Rachel,Inglese, James,Du, Yuchun,Demangel, Caroline,High, Stephen,Paavilainen, Ville O.,Shi, Wei Q.
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supporting information
p. 8450 - 8461
(2019/06/04)
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- Structure-based design and synthesis of new 4-methylcoumarin-based lignans as pro-inflammatory cytokines (TNF-α, IL-6 and IL-1β)inhibitors
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Suppression of pro-inflammatory cytokines (TNF-α, IL-1β and IL-6)along with nitric oxide reduction in RAW 264.7 cells by 7,8-dihydroxy-4-methylcoumarin, ethyl p-coumarate, ethyl caffeate and ethyl ferulate drove us to search structural-analogues of the aforementioned compounds through structure-based drug design. Docking studies revealed that substituted cinnamic acids and their ethyl esters (2-7c)showed higher GoldScore-fitness (GSF)and non-bonding interactions with target proteins than 7,8-dihydroxy-4-methylcoumarin (1a)and 7,8-dihydroxy-5-methylcoumarin (1b). With this background, the methylcoumarins (1a and 1b)and the cinnamic acid derivatives (2-7c)were fused in different permutations and combinations to generate sixty novel fused-cyclic coumarinolignans (FCLs)(8–13k). Docking studies on 8–13k indicated that several FCLs possess higher GSF, interesting active site interactions and distinctive π-π interactions compared to the standards (cleomiscosin A, diclofenac Na and prednisolone). Based on these findings, four novel FCLs (9d, 10d, 11d and 11e)were synthesized and tested for inhibition effect on TNF-α, IL-1β and IL-6 expressions in LPS and oxalate crystal-induced in-vitro models. Compound 10d exhibited significant effect (P 50 value of 8.5 μM against TNF-α. Compound 11e possessed IC50 values of 13.29 μM and 17.94 μM against IL-6 and IL-1β, respectively. Study on SAR corroborated the requirement of C-4-methyl substituent in the coumarin moiety, dihydroxyl groups in the phenyl ring, and esterification of lignans for potent activity. Additionally, the reported excellent anti-inflammatory activity of cleomiscosin-A-glucoside was corroborated by from the higher GSF and better hydrophobic interactions than cleomsicosin A in the docking study. As an outcome, some novel and potentially active FCLs acting through NFκB and caspase 1 signaling pathways have been discovered as multiple cytokine inhibitors.
- Santhosh Kumar,Sajeli Begum, Ahil,Hira, Kirti,Niazi, Sarfaraj,Prashantha Kumar,Araya, Hiroshi,Fujimoto, Yoshinori
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- Method for synthesizing alkyne through catalytic asymmetric cross coupling (by machine translation)
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The invention belongs to the field of, asymmetric synthesis, and discloses a method for catalyzing asymmetric cross- coupling to synthesize: an alkyne, and the L method comprises, the following steps, of A: preparing B a cuprous, salt and C a: ligand; preparing a catalyst; adding a base; reacting the compound with the compound with the compound; and reacting the compound with the compound. Of these, one of them, X is selected from the group consisting of, R halogens. 1 Optionally substituted heteroarylsulfonylcyanamide groups selected from the, group consisting, of optionally substituted, phenyl groups In-flight vehicle, R6 Trialkyl silyl groups or alkyl radicals, R2 Cycloalkyl radicals optionally substituted with an, optionally substituted alkyl, (CH radical2 )n R4 Multi,layer chain, n＝0-10,R saw blade4 A group selected, from, the group consisting of phenyl, alkenyl, aralkynyls, noonyloxy,and, noonylsulfonylsulfonylsulfonylsulfonylsulfonylsulfonylsulfonylsulfonylsulfonylsulphonylsulphonylsulphonylsulphonylsulphonylsulphonylsulphonylsulphonylsulphonylsulphonylphenyl disiloxy-radicals. R3 A ligand, selected from hydrogen or any of the functional groups, is selected from the group consisting of, hydrogen and any L other functional group. The method, R disclosed by the, A invention has the, advantages of good catalytic, R ’ effect, wide application range. and high catalytic efficiency, and the, method disclosed by the, invention has the. advantages of good catalytic effect, wide application range and high catalytic efficiency. (by machine translation)
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Paragraph 1011; 1019-1021
(2020/01/12)
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- Method for synthesizing AMG837
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The invention relates to a method for synthesizing a compound, in particular to a method for synthesizing AMG837. The method comprises the following steps: a step of preparing an intermediate D by a reaction of an intermediate E with propyne; a step of de
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Paragraph 0054; 0070-0074
(2020/01/03)
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- Pd-chelated 1,3,5-triazine organosilica as an active catalyst for Suzuki and Heck reactions
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Design of novel functional periodic mesoporous organosilica with molecular level control finds applications in several fields of energy and environmental research including adsorption, catalysis, nanotechnology, and energy harvesting. Herein we present a melamine (1,3,5-triazine) functionalized periodic mesoporous silica (MPMO) by self-assembly of N2,N4,N6-tris(3-(triethoxysilyl)propyl)-1,3,5-triazine-2,4,6-triamine (TTET) with tetraethylorthosilicate (TEOS) via cocondensation strategy. The TTET silsesquioxane precursor was synthesized by the condensation reaction between cyanuric chloride and 3-aminopropyl triethoxysilane. The resultant MPMO material serves as an effective solid chelating agent through amine and triazine functionalities for Pd(II) to provide Pd-MPMO. The Pd-MPMO material was thoroughly characterized by a small-angle XRD, HRTEM, N2 sorption, 13C CP-MAS NMR, 29Si CP-MAS NMR, and ICP analyses. The Pd-MPMO serves as an active catalyst for C–C bond formation reactions by Suzuki- and Heck cross-coupling methodologies under ligand- and cocatalyst-free conditions. Notably, the present catalytic protocol demonstrates a wide spectrum of substrate scope towards Suzuki coupling between aryl halides (I?, Br?, Cl?) and aryl boronic acids with high turn-over-number (TON) in aqueous phase under air ambience. Whereas for Heck-coupling reaction, the phenyl iodides furnished high TON than the other aryl halides. Investigation of Pd-leaching by a hot filtration test as well as reusability experiments confirms the true heterogeneous nature of present Pd-MPMO and its robustness in terms of substrate scope, catalyst stability, and durability.
- Elavarasan,Kala,Muhammad, Ibrahim,Bhaumik,Sasidharan
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- In-vitro and in-vivo antimalarial activity of caffeic acid and some of its derivatives
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Objectives: To explore the in-vitro and in-vivo antimalarial potential of caffeic acid and derivatives. Methods: Two common phenolic acids (caffeic acid and chlorogenic acid) were evaluated for in-vitro and in-vivo antiplasmodial activity in comparison with some semi-synthetic derivatives that were synthesized. An in-vitro assay based on plasmodial lactate dehydrogenase activity, and the classical in-vivo 5-day suppressive test from Peters on an artemisinin-resistant Plasmodium berghei strain was used. Parasitic stage sensitivity to ethyl caffeate was determined in this work. Key findings: Phenolic acid esters derivatives showed better antiplasmodial activity than corresponding phenolic acids. The derivative with the highest in-vitro activity being caffeic acid ethyl ester, exhibiting an IC50?=?21.9?±?9.4?μm. Ethyl caffeate and methyl caffeate were then evaluated for antimalarial activity in?vivo and ethyl caffeate showed a growth inhibition of 55% at 100?mg/kg. Finally, it seems that ethyl caffeate blocks the growth of young parasitic forms. Conclusions: Our study provides evidence for an antimalarial potential of caffeic acid derivatives which are common in several medicinal plants traditionally used against malaria. It also demonstrates the possibility to use such derivatives in the treatment of malaria.
- Alson, Sylvain G.,Jansen, Olivia,Cieckiewicz, Ewa,Rakotoarimanana, Hajatiana,Rafatro, Herintsoa,Degotte, Gilles,Francotte, Pierre,Frederich, Michel
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p. 1349 - 1356
(2018/07/31)
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- Acylating p-hydroxyl cinnamate plasticizer and preparation method thereof
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The invention discloses an acylating p-hydroxyl cinnamate plasticizer as shown in formula (I) and a preparation method for the acylating p-hydroxyl cinnamate plasticizer. The preparation method for the acylating p-hydroxyl cinnamate plasticizer comprises
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Paragraph 0044
(2018/03/26)
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- Diamine compound
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Provided is a liquid crystal orientation agent comprising at least one polymer selected from polyimide precursors obtained by reacting an amine component comprising a diamine compound represented by formula [1] and a tetracarboxylic dianhydride component, and polyimides obtained by imidation of the same. [1] (In the formula, R3 is a group selected from -CH2-, -O-, -CONH-, -NHCO-, -COO-, -OCO-, -NH-, and -CO-. R4 is a C1-30 alkylene group, divalent carbon ring, or heterocycle, and one or a plurality of the hydrogen atoms of the alkylene group, divalent carbon ring, or heterocycle can be optionally substituted by fluorine atoms or organic groups. Moreover, when there are adjacent -O-, -NHCO-, -CONH-, -COO-, -OCO-, -NH-, or -CO-, R4 can be such that these adjacent groups are substituted by -CH2-. R5 is -CH2-, -O-, -CONH-, -NHCO-, -COO-, -OCO-, -NH-, -CO-, or a single bond. R6 is a group that goes through photodimerization. R7 is a single bond or a C1-30 alkylene group, divalent carbon ring, or heterocycle, and one or a plurality of the hydrogen atoms of the alkylene group, divalent carbon ring, or heterocycle can be substituted by fluorine atoms or organic groups. Moreover, when there are adjacent -O-, -NHCO-, -CONH-, -COO-, -OCO-, -NH-, or -CO-, R7 can be such that these adjacent groups are substituted by -CH2-. R8 is a photopolymerizable group.)
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Paragraph 0153-0156
(2018/10/03)
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- Exploration of phenylpropanoic acids as agonists of the free fatty acid receptor 4 (FFA4): Identification of an orally efficacious FFA4 agonist
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The long chain free fatty acid receptor 4 (FFA4/GPR120) has recently been recognized as lipid sensor playing important roles in nutrient sensing and inflammation and thus holds potential as a therapeutic target for type 2 diabetes and metabolic syndrome. To explore the effects of stimulating this receptor in animal models of metabolic disease, we initiated work to identify agonists with appropriate pharmacokinetic properties to support progression into in vivo studies. Extensive SAR studies of a series of phenylpropanoic acids led to the identification of compound 29, a FFA4 agonist which lowers plasma glucose in two preclinical models of type 2 diabetes.
- Sparks, Steven M.,Aquino, Christopher,Banker, Pierette,Collins, Jon L.,Cowan, David,Diaz, Caroline,Dock, Steven T.,Hertzog, Donald L.,Liang, Xi,Swiger, Erin D.,Yuen, Josephine,Chen, Grace,Jayawickreme, Channa,Moncol, David,Nystrom, Christopher,Rash, Vincent,Rimele, Thomas,Roller, Shane,Ross, Sean
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p. 1278 - 1283
(2017/06/19)
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- Transition Metal Free C-N Bond Forming Dearomatizations and Aryl C-H Aminations by in Situ Release of a Hydroxylamine-Based Aminating Agent
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We outline a simple protocol that accesses directly unprotected secondary amines by intramolecular C-N bond forming dearomatization or aryl C-H amination. The method is dependent on the generation of a potent electrophilic aminating agent released by in situ deprotection of O-Ts activated N-Boc hydroxylamines.
- Farndon, Joshua J.,Ma, Xiaofeng,Bower, John F.
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supporting information
p. 14005 - 14008
(2017/10/17)
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- A Simple and Broadly Applicable C?N Bond Forming Dearomatization Protocol Enabled by Bifunctional Amino Reagents
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A C?N bond forming dearomatization protocol with broad scope is outlined. Specifically, bifunctional amino reagents are used for sequential nucleophilic and electrophilic C?N bond formations, with the latter effecting the key dearomatization step. Using t
- Ma, Xiaofeng,Farndon, Joshua J.,Young, Tom A.,Fey, Natalie,Bower, John F.
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supporting information
p. 14531 - 14535
(2017/10/18)
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- S,O-Ligand-Promoted Palladium-Catalyzed C-H Functionalization Reactions of Nondirected Arenes
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Pd(II)-catalyzed C-H functionalization of nondirected arenes has been realized using an inexpensive and easily accessible type of bidentate S,O-ligand. The catalytic system shows high efficiency in the C-H olefination reaction of electron-rich and electron-poor arenes. This methodology is operationally simple, scalable, and can be used in late-stage functionalization of complex molecules. The broad applicability of this catalyst has been showcased in other transformations such as Pd(II)-catalyzed C-H acetoxylation and allylation reactions.
- Naksomboon, Kananat,Valderas, Carolina,Gómez-Martínez, Melania,álvarez-Casao, Yolanda,Fernández-Ibá?ez, M. ángeles
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p. 6342 - 6346
(2017/09/15)
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- Bioactivity and structure-activity relationship of cinnamic acid esters and their derivatives as potential antifungal agents for plant protection
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A series of cinnamic acid esters and their derivatives were synthesized and evaluated for antifungal activities in vitro against four plant pathogenic fungi by using the mycelium growth rate method. Structure-activity relationship was derived also. Almost all of the compounds showed some inhibition activity on each of the fungi at 0.5 mM. Eight compounds showed the higher average activity with average EC50 values of 17.4-28.6 μg/mL for the fungi than kresoxim-methyl, a commercial fungicide standard, and ten compounds were much more active than commercial fungicide standards carbendazim against P. grisea or kresoxim-methyl against both P. grisea and Valsa Mali. Compounds C1 and C2 showed the higher activity with average EC50 values of 17.4 and 18.5 μg/mL and great potential for development of new plant antifungal agents. The structure-activity relationship analysis showed that both the substitution pattern of the phenyl ring and the alkyl group in the alcohol moiety significantly influences the activity. There exists complexly comprehensive effect between the substituents on the phenyl ring and the alkyl group in the alcohol moiety on the activity. Thus, cinnamic acid esters showed great potential the development of new antifungal agents for plant protection due to high activity, natural compounds or natural compound framework, simple structure, easy preparation, low-cost and environmentally friendly.
- Zhou, Kun,Chen, Dongdong,Li, Bin,Zhang, Bingyu,Miao, Fang,Zhou, Le
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- Palladium-Catalyzed Directed para C?H Functionalization of Phenols
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Various practical methods for the selective C?H functionalization of the ortho and recently also of the meta position of an arene have already been developed. Following our recent development of the directing-group-assisted para C?H functionalization of toluene derivatives, we herein report the first remote para C?H functionalization of phenol derivatives by using a recyclable silicon-containing biphenyl-based template. The effectiveness of this strategy was illustrated with different synthetic elaborations and by the synthesis of various phenol-based natural products.
- Patra, Tuhin,Bag, Sukdev,Kancherla, Rajesh,Mondal, Anirban,Dey, Aniruddha,Pimparkar, Sandeep,Agasti, Soumitra,Modak, Atanu,Maiti, Debabrata
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supporting information
p. 7751 - 7755
(2016/07/07)
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- Synthesis and anticancer activities of glycyrrhetinic acid derivatives
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A total of forty novel glycyrrhetinic acid (GA) derivatives were designed and synthesized. The cytotoxic activity of the novel compounds was tested against two human breast cancer cell lines (MCF-7, MDA-MB-231) in vitro by the MTT method. The evaluation results revealed that, in comparison with GA, compound 42 shows the most promising anticancer activity (IC50 1.88 ± 0.20 and 1.37 ± 0.18 μM for MCF-7 and MDA-MB-231, respectively) and merits further exploration as a new anticancer agent.
- Li, Yang,Feng, Ling,Song, Zhi-Fang,Li, Hai-Bei,Huai, Qi-Yong
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- Preparation method of neoflavonoids
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The invention relates to the field of chemical synthesis, in particular to a preparation method of neoflavonoids. The preparation method is characterized by comprising the following steps of using substituted benzaldehyde as an initial raw material to be reacted with malonic acid to generate a substituted phenylacrylic acid compound; performing an addition reaction, an elimination reaction and the like on the substituted phenylacrylic acid compound, or performing acetylation so as to protect a phenolic hydroxyl group, then performing a bromination reaction and the elimination reaction so as to synthesize the substituted phenylpropiolic acid compound ; and using montmorillonite K-10 after being acidulated by sulfuric acid as a catalyst, enabling the substituted phenylpropiolic acid compound and a phenolic compound to perform a heating reaction so as to generate the neoflavonoids. Compared with the prior art, the preparation method of the neoflavonoids, disclosed by the invention, has the characteristics that raw materials are cheap, and easy to obtain, the operation is simple, the catalyst can be recovered for use, and the method is environmentally-friendly, the post-treatment is simple, and the production cost is low, and the method has a high popularization and application value.
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Paragraph 0107
(2017/04/26)
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- Discovery of neurotrophic agents based on hydroxycinnamic acid scaffold
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The number of people affected by neurodegenerative disorders such as Alzheimer's disease and Parkinson's disease is rapidly increasing owing to the global increase in life expectancy. Small molecules with neurotrophic effects have great potential for management of these neurological disorders. In this study, different (C1–C12) alkyl ester derivatives of hydroxycinnamic acids (HCAs) were synthesized (a total of 30 compounds). The neurotrophic capacity of the test compounds was examined by measuring promotion of survival in serum-deprived conditions and enhancement of nerve growth factor (NGF)-induced neurite outgrowth in PC12 neuronal cells. p-Coumaric, ferulic, and sinapic acids and their esters did not alter cell survival, while caffeic acid and all its alkyl esters, especially decyl and dodecyl caffeate, significantly promoted neuronal survival at 25?μm. Methyl, ethyl, propyl, and butyl caffeate esters also significantly enhanced NGF-induced neurite outgrowth, among which the most effective ones were propyl and butyl esters, which at 5?μm led to 25- and 22-fold increases in the number of neurites, respectively. The findings of the docking study suggested phosphatidylinositol 3-kinase (PI3K) as the potential molecular target. In conclusion, our findings demonstrate that alkyl esters of caffeic acid can be useful as scaffolds for the discovery of therapeutic agents for neurodegenerative diseases.
- Hosseini, Razieh,Moosavi, Fatemeh,Rajaian, Hamid,Silva, Tiago,Magalh?es e Silva, Diogo,Soares, Pedro,Saso, Luciano,Edraki, Najmeh,Miri, Ramin,Borges, Fernanda,Firuzi, Omidreza
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p. 926 - 937
(2016/11/11)
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- Synthesis of tetrahydropyranyl diarylheptanoids from Dioscorea villosa
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Concise syntheses of four tetrahydropyranyl diarylheptanoids isolated from Dioscorea villosa have been described. The key features include Prins cyclization to construct the tetrahydropyran cores, Keck asymmetric allylation, and Mitsunobu inversion. Optimization of the Prins cyclization conditions in order to minimize racemization has been described. Our syntheses also confirmed the absolute stereochemistry of the natural products.
- Kantee, Kawalee,Rukachaisirikul, Vatcharin,Tadpetch, Kwanruthai
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supporting information
p. 3505 - 3509
(2016/07/15)
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- Ligand-Free Heck Reactions of Aryl Iodides: Significant Acceleration of the Rate through Visible Light Irradiation at Ambient Temperature
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A mild Heck reaction of aryl iodides and olefins was realized by the cooperation of a palladium and a photoredox catalyst under the irradiation of visible light. This protocol works well to synthesize stilbenes with high Z/E ratios and (E)-cinnamates in the absence of ligands at ambient temperature. Control experiments revealed that palladium salt, visible light and photoredox catalyst were all crucial for the achievement of this cross-coupling under mild conditions. (Figure presented.).
- Zhang, Heng,Huang, Xueliang
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supporting information
p. 3736 - 3742
(2016/12/16)
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- Quantitative Structure-Property Relationship (QSPR) models for a local quantum descriptor: Investigation of the 4- and 3-substituted-cinnamic acid esterification
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In this work, the theoretical description of the 4- and 3-substituted-cinnamic acid esterification with different electron donating and electron withdrawing groups was performed at the B3LYP and M06-2X levels, as a two-step process: the O-protonation and the nucleophile attack by ethanol. In parallel, an experimental work devoted to the synthesis and characterization of the substituted-cinnamate esters has also been performed. In order to quantify the substituents effects, quantitative structure-property relationship (QSPR) models based on the atomic charges, Fukui functions and the Frontier Effective-for-Reaction Molecular Orbitals (FERMO) energies were investigated. In fact, the Fukui functions, f+C and f-O, indicated poor correlations for each individual step, and in contrast with the general literature, the O-protonation step is affected both by the FERMO energies and the O-charges of the carbonyl group. Since the process was shown to not be totally described by either charge- or frontier-orbitals, it is proposed to be frontier-charge-miscere controlled. Moreover, the observed trend for the experimental reaction yields suggests that the electron withdrawing groups favor the reaction and the same was observed for Step 2, which can thus be pointed out as the determining step.
- Rodrigues-Santos, Cláudio E.,Echevarria, Aurea,Sant'Anna, Carlos M.R.,Bitencourt, Thiago B.,Nascimento, Maria G.,Bauerfeldt, Glauco F.
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supporting information
p. 17493 - 17510
(2015/12/01)
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- Sensomics Analysis of Key Bitter Compounds in the Hard Resin of Hops (Humulus lupulus L.) and Their Contribution to the Bitter Profile of Pilsner-Type Beer
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Recent brewing trials indicated the occurrence of valuable bitter compounds in the hard resin fraction of hop. Aiming at the discovery of these compounds, hop's ε-resin was separated by means of a sensory guided fractionation approach and the key taste mo
- Dresel, Michael,Dunkel, Andreas,Hofmann, Thomas
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p. 3402 - 3418
(2015/04/14)
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- Ethyl cinnamate derivatives as promising high-efficient acaricides against Psoroptes cuniculi: Synthesis, bioactivity and structure-activity relationship
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This paper reported the synthesis, structure-activity relationship (SAR) and acaricidal activity in vitro against Psoroptes cuniculi, a mange mite, of 25 ethyl cinnamate derivatives. All target compounds were synthesized and elucidated by means of MS, 1H- and 13C-NMR analysis. The results showed that 24 out of 25 tested compounds at 1.0 mg/mL demonstrated acaricidal activity in varying degrees. Among them, 6, 15, 26, 27 and 30 showed significant activity with median lethal concentration values (LC50) of 89.3, 119.0, 39.2, 29.8 and 41.2 μg/mL, respectively, which were 2.1- to 8.3-fold the activity of ivermectin (LC50=247.4 μg/mL), a standard drug in the treatment of Psoroptes cuniculi. Compared with ivermectin, with a median lethal time value (LT50) of 8.9 h, 27 and 30 showed smaller LTM50 values of 7.9 and 1.3 h, respectively, whereas 6, 15 and 26 showed slightly larger LT50 values of 10.6, 11.0 and 10.4 h at 4.5 μmol/mL. SARs showed that the presence of o-NO2 or m-NO2 on the benzene ring significantly improved the activity, whereas the introduction of a hydroxy, methoxy, acetoxy, methylenedioxy, bromo or chloro group reduced the activity. (E)-Cinnamates were more effective than their (Z)-isomer. Nevertheless, the carbon-carbon double bond in the acrylic ester moiety was proven not to be essential to improve the activity of cinnamic acid esters. Thus, the results strongly indicate that cinnamate derivatives, especially their dihydro derivatives, should be promising candidates or lead compounds for the development of novel acaricides for the effective control of animal or human acariasis.
- Zhang, Bingyu,Lv, Chao,Li, Weibo,Cui, Zhiming,Chen, Dongdong,Cao, Fangjun,Miao, Fang,Zhou, Le
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p. 255 - 262
(2015/04/22)
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- Ligand-free C-C and C-N cross-couplings with Pd/Nf-G nanocomposite
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Abstract The catalytic activity of electrochemical deposited Pd nanoparticles on nafion-graphene support was examined for Buchwald-Hartwig amination reaction and Heck coupling reaction. The developed protocol is very efficient and ecofriendly, providing excellent product yield. The Pd/Nf-G catalyst can be used up to four cycles with slight decrease in catalytic activity.
- Shelkar, Radheshyam S.,Shendage, Suresh S.,Nagarkar, Jayashree M.
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supporting information
p. 4463 - 4467
(2015/06/30)
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- Synthesis of alkyl coumarate esters by celite-bound lipase of Bacillus licheniformis SCD11501
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Coumaric acid and its derivatives are known to inhibit UV-induced melanogenesis, skin erythema, angiogenesis, platelet accumulation and osteoclastogenesis besides regulation of bone formation, anti-oxidant and anti-microbial activities. The present study is a novel piece of work in which the syntheses of a series of alkyl coumarates (methyl coumarate, ethyl coumarate, propyl coumarate and butyl coumarate) have been achieved using celite-immobilized lipase of Bacillus licheniformis strain SCD11501 in a water-free medium at 55 C under shaking in a chemical reactor. The maximum yield(s) of coumaric acid based esters i.e. methyl coumarate (69.0%), ethyl coumarate (63.1%), n-propyl coumarate (59.8%) and n-butyl coumarate (55.1%) using celite-immobilized lipase could be achieved after optimizing various reaction parameters such as incubation time, incubation temperature, relative molar concentration of reactants, biocatalyst concentration and amount of molecular sieves added to the reaction system. Molecular sieves had an important effect on the ester synthesis resulting in an enhanced yield. Maximum yield was recorded for methyl coumarate (69.0%) possibly because methyl group causes less stearic hindrance to the catalytic site of the lipase due to which it becomes more accessible for immobilized lipase to undergo esterification. The characterization of synthesized esters was done through FTIR spectroscopy and 1H NMR spectra.
- Sharma, Shivika,Dogra, Priyanka,Chauhan, Ghanshyam S.,Kanwar, Shamsher S.
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- Synthesis of neolignans as microtubule stabilisers
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Tubulin is a well established target for anticancer drug development. Lignans and neolignans were synthesized as tubulin interacting agents. Neolignans 10 and 19 exhibited significant anticancer activity against MCF-7 and MDAMB-231 human breast cancer cell lines. Both the compounds effectively induced stabilization of microtubule at 4 and 20 μM concentrations respectively. Neolignan 10 induced G2/M phase arrest in MCF-7 cells. Docking experiments raveled that 10 and 19 occupied the same binding pocket of paclitaxel with some difference in active site amino acids and good bioavailability of both the compounds. In in vivo acute oral toxicity 10 was well tolerated up to 300 mg/kg dose in Swiss-albino mice.
- Sathish Kumar,Singh, Aastha,Kumar, Amit,Singh, Jyotsna,Hasanain, Mohammad,Singh, Arjun,Masood, Nusrat,Yadav, Dharmendra K.,Konwar, Rituraj,Mitra, Kalyan,Sarkar, Jayanta,Luqman, Suaib,Pal, Anirban,Khan, Feroz,Chanda, Debabrata,Negi, Arvind S.
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p. 1342 - 1354
(2014/03/21)
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- Nano Pd-Fe3O4@Alg beads: As an efficient and magnetically separable catalyst for Suzuki, Heck and Buchwald-Hartwig coupling reactions
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Catalytic processes are the backbone of many chemical industries. In a comparative study of various heterogeneous catalytic systems, we report efficient and magnetically separable nano Pd-Fe3O4@Alg beads as catalysts for Suzuki, Heck and Buchwald-Hartwig coupling reactions. This catalyst was characterized by SEM, TEM, HRTEM, XRD, EDAX, FT-IR, VSM, DSC-TGA, BET, and UV-Visible spectroscopy. This heterogeneous catalyst showed high catalytic activity and stability for C-C and C-N bond forming coupling reactions with excellent product yield under ligand free conditions. The beads of nano Pd-Fe3O4@Alg can be separated from the reaction mixture by an external magnet and reused for several successive cycles with no appreciable loss in the catalytic activity. The Suzuki and Heck coupling reactions in aqueous medium are greener routes, which is an added advantage of this protocol. This journal is
- Shelkar, Radheshyam S.,Gund, Sitaram H.,Nagarkar, Jayashree M.
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p. 53387 - 53396
(2015/02/05)
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- Palladium supported on zinc oxide nanoparticles: Synthesis, characterization, and application as heterogeneous catalyst for Mizoroki-Heck and Sonogashira reactions under ligand-free and air atmosphere conditions
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In this paper, a novel Palladium (Pd) supported on ZnO nanoparticles was readily synthesized and characterized by using X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and BET specific surface area measurement. The total amount of palladium particles on ZnO was determined by induced coupled plasma (ICP) analysis and atomic absorption spectroscopy (AAS) which is 9.8 wt%. Percentage of accessible Pd as active catalyst is also estimated to 2.72% based on the thermogravimetric (TG) analysis. Nano Pd/ZnO was found as a new, novel, and excellent heterogeneous catalyst for ligand-free C-C bond formation through the Mizoroki-Heck and Sonogashira reactions under air atmosphere without the use of any Ar or N2 flow. The catalyst can be recovered and recycled several times without marked loss of activity.
- Hosseini-Sarvari, Mona,Razmi, Zahra,Doroodmand, Mohammad Mehdi
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p. 477 - 486
(2014/03/21)
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- Mono-/dihydroxybenzoic acid esters and phenol pyridinium derivatives as inhibitors of the mammalian carbonic anhydrase isoforms I, II, VII, IX, XII and XIV
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Using hydroxy-/dihydroxybenzoic acids as leads, a series of methyl, ethyl and iso-propyl esters of 4-hydroxy-benzoic acid, 2,4-, 2,5-, 2,6-, 3,4-, and 3,5-dihydroxybenzoic acids and of coumaric acid, were obtained and investigated for the inhibition of six mammalian carbonic anhydrase (CA, EC 4.2.1.1) isoforms, that is, the cytosolic CA I, II and VII, and the transmembrane CA IX, XII and XIV, many of which are established drug targets. Other compounds incorporating phenol/catechol moieties were obtained from dopamine by reaction with fluorescein isothiocyanate or with 2,4,6-trisubstituted pyrylium salts. Some aminophenols were also derivatized in a similar manner, by using pyrylium salts. Many of these compounds showed increased inhibitory action compared to the lead compounds from which they were obtained, with efficacy in the submicromolar range against most investigated CA isoforms. As phenols are a class of less investigated CA inhibitors (CAIs) compared to the sulfonamides, and their mechanism of inhibition is less well understood, compounds of the type designed here may be helpful in gaining more insights into these phenomena.
- Carta, Fabrizio,Vullo, Daniela,Maresca, Alfonso,Scozzafava, Andrea,Supuran, Claudiu T.
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supporting information
p. 1564 - 1569
(2013/04/10)
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- Nitric oxide donating anilinopyrimidines: Synthesis and biological evaluation as EGFR inhibitors
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To search for potent nitric oxide (NO) donating epidermal growth factor receptor (EGFR) inhibitors, a series of phenylsulfonylfuroxan-based anilinopyrimidines 10a-h were synthesized and biologically evaluated. Compounds 10f-h exhibited potent inhibitory activity against EGFR L858R/T790M and were as potent as WZ4002 in inhibition of H1975 cells harboring EGFR L858R/T790M. Additionally, 10h produced high levels of NO in H1975 cells but not in normal human cells, and its antiproliferative activity was diminished by hemoglobin, an NO scavenger. Furthermore, 10h inhibited EGFR activation and downstream signaling in H1975 cells. These results suggest that the strong antiproliferative activity of 10h could be attributed to the synergic effects of high levels of NO production and inhibition of EGFR and downstream signaling in the cancer cells.
- Han, Chun,Huang, Zhangjian,Zheng, Chao,Wan, Ledong,Lai, Yisheng,Peng, Sixun,Ding, Ke,Ji, Hongbin,Zhang, Yihua
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- Synthesis of a novel 8-hydroxyquinoline functionalized poly (ethylene glycol) bridged dicationic ionic liquid and its application in palladium-catalyzed Heck reaction under solvent-free conditions
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A novel 8-hydroxyquinoline functionalized poly (ethylene glycol) bridged dicationic ionic liquid ([HQ-PEG1000-DIL][BF4]) was synthesized and characterized. It was applied as an efficiently recyclable ligand for Pd-catalyzed Heck reaction under solvent-free conditions. It is noteworthy that the Pd(OAc)2/[HQ-PEG1000-DIL][BF 4] catalytic system could be easily recovered and reused without obvious loss of catalytic activity after five recycling runs.
- Wang, Yinglei,Luo, Jun,Liu, Zuliang
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- Palladium supported on zinc ferrite: An efficient catalyst for ligand free C-C and C-O cross coupling reactions
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An efficient superparamagnetic Pd-ZnFe2O4 solid catalyst has been synthesized by loading Pd(0) species on zinc ferrite nanoparticles. Sonogashira cross couplings between terminal alkynes and aryl halides were achieved in the absence of any Cu co-catalyst. A Heck-Matsuda coupling reaction of structurally different aryldiazonium tetrafluoroborate substrates was preceded at 40 C in water. Cyanation of aryl halides was successfully done using K4[Fe(CN)6] as the cyanide source over Pd-ZnFe2O4. The catalyst was also employed for Ullmann type cross coupling reactions. Excellent yield of the products, reusability, and uncomplicated work-up make this catalyst efficient for C-C and C-O coupling reactions. Good yield of products, easy separation, and negligible leaching of Pd from the catalyst surface confirm the true heterogeneity in these catalytic reactions.
- Singh, Abhilash S.,Shendage, Suresh S.,Nagarkar, Jayashree M.
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p. 6319 - 6323
(2013/11/06)
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- One-pot preparation of phenylpropanoid esters co-catalyzed by boric acid and piperidine
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Phenylpropanoid esters, especially those with hydroxyl and/or methoxy groups on the benzene ring, are important medicinal chemicals or intermediates. They are usually prepared by esterification of their corresponding substituted cinnamic acids with various alcohols. However, the esterification procedures often suffer from environmentally hazardous problems when sulfuric acid is used as a catalyst or suffer from unsatisfactory yields and expensive raw material when enzyme is applied as a catalyst. In this paper, a convenient one-pot process for preparing various phenylpropanoid esters from substituted benzaldehydes bearing hydroxyl and/or methoxyl groups has been developed. The alcohols react first with malonic acid catalyzed by boric acid to form monomalonate, then without separation, let the resultant mixture immediately react with the injected various substituted benzaldehydes in the presence of piperidine to afford the desired esters with moderate to good yields. Springer Science+Business Media B.V. 2011.
- Wang, Huan,Wei, Qing-Yi,Jiang, Hong,Jiang, Zhen-Hua
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experimental part
p. 207 - 213
(2012/05/20)
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- Solid supported palladium(0) nano/microparticle: A ligand-free efficient recyclable heterogeneous catalyst for mono- and β,β-double-Heck reaction
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Solid supported palladium nano/microparticles were found to be active catalysts to perform mono- and β,β-double-Heck reactions. Different β-unsubstituted and substituted alkenes including acrylate, methacrylate, crotonate, styrene, acrylonitrile, and acrylamide were investigated successfully for mono- and β,β-double-Heck reactions with aryl iodide under milder reaction condition. One-pot β,β-double-Heck reaction of aryl iodides with α,β-unsaturated ester, amide, nitrile, and styrene derivatives were also performed under standard reaction conditions. Wide functional group tolerance, easy catalyst recovery, and recyclability up to twelve times without significant loss of catalytic activity added extra importance to the present process.
- Sharma, Dharminder,Kumar, Sandeep,Shil, Arun K.,Guha, Nitul Ranjan,Bandna,Das, Pralay
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supporting information
p. 7044 - 7051
(2013/01/15)
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- Tandem heck/decarboxylation/heck strategy: Protecting-group-free synthesis of symmetric and unsymmetric hydroxylated stilbenoids
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Ride the (micro)wave: The title strategy has been developed for the synthesis of various symmetric or unsymmetric hydroxylated stilbenoids utilizing 4-halophenols and acrylic acid as coupling partners (see scheme; DMA=N,N-dimethylacetamide, MW=microwave). Protecting groups are not necessary and a single palladium catalyst is used. Copyright
- Shard, Amit,Sharma, Naina,Bharti, Richa,Dadhwal, Sumit,Kumar, Rajesh,Sinha, Arun K.
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supporting information
p. 12250 - 12253
(2013/02/22)
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- Ligustrazine derivatives. Part 5: Design, synthesis and biological evaluation of novel ligustrazinyloxy-cinnamic acid derivatives as potent cardiovascular agents
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A series of novel ligustrazinyloxy-cinnamic acid derivatives were designed, synthesized and evaluated for their inhibitory effect on adenosine diphosphate (ADP)-induced platelet aggregation in vitro, and also assayed for their protective effect against hydrogen peroxide (H2O2)-induced oxidative damage on ECV-304 cells. Some compounds exhibited high activity in one or both of the assays, of which, compound 2e displayed the highest protective effect on the proliferation of the damaged ECV-304 cells (EC 50 = 0.020 mM), and compound 2f was the most active anti-platelet aggregation agent (EC50 = 0.054 mM). Structure-activity relationships were briefly discussed.
- Chen, Hongfei,Li, Guoning,Zhan, Peng,Liu, Xinyong
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experimental part
p. 5609 - 5615
(2012/01/03)
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- Organocatalytic decarboxylative Doebner-Knoevenagel reactions between arylaldehydes and monoethyl malonate mediated by a bifunctional polymeric catalyst
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A bifunctional polystyrene bearing both DMAP and piperidine groups has been prepared and used as an organocatalyst for decarboxylative Doebner-Knoevenagel reactions of arylaldehydes and monoethyl malonate. Isolated yields of the resulting cinnamates were very high, and in all cases only the E-isomer was detected. When a polystyrene catalyst functionalized with only DMAP or piperidine groups was used in these reactions, catalysis was much less efficient. Furthermore, catalysis using a combination of the monofunctional polymers was also less efficient than with the bifunctional polystyrene. Thus, it appears that there is a synergistic effect obtained by co-locating the two different catalytic amine groups on the same polymer backbone. Georg Thieme Verlag Stuttgart · New York.
- Lu, Jinni,Toy, Patrick H.
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supporting information; experimental part
p. 1723 - 1726
(2011/09/12)
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