- Synthesis, characterization and cytotoxicity of platinum(II)/palladium(II) complexes with 1,3-diaminopropane and 4-toluensulfonyl-l-amino acid dianion
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Eight novel platinum(II)/palladium(II) complexes with 1,3-dap and 4-toluensulfonyl-l-amino acid dianion, [Pt(1,3-dap)(TsalaNO)]·0.5H 2O (1a), [Pt(1,3-dap)(TsvalNO)] (1b), [Pt(1,3-dap)(TspheNO)] (1c), [Pt(1,3-dap)(TsserNO)] (1d), [Pd(1,3-dap)(Ts
- Zhang, Jinchao,Ma, Lili,Lu, Huiru,Wang, Yuechai,Li, Shenghui,Wang, Shuxiang,Zhou, Guoqiang
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- Synthesis, characterization and cytotoxicity of mixed-ligand complexes of palladium(II) with aromatic diimine and 4-toluenesulfonyl-l-amino acid dianion
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Eight new palladium(II) complexes (1a-2d) with 4-toluenesulfonyl-l-amino acid dianion and diimine (bipy and phen) have been synthesized and characterized by elemental analysis, IR, UV, 1H NMR, 13C NMR and mass spectra techniques. Cry
- Zhang, Jinchao,Li, Luwei,Wang, Liwei,Zhang, Fangfang,Li, Xiaoliu
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- Synthesis and Structural Characterization of Trivalent Amino Acid Derived Chiral Phosphorus Compounds
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Reaction of the N-toluenesulfonyl derivatives of (S)-alanine, phenylalanine, and valine (4-6) with PhPCl2 gave in high yield the 4-methyl, benzyl, and isopropyl derivatives (7-9) of 2-phenyl-1-p-toluenesulfonyl-1,3,2-oxazaphospholidin-5-one. Th
- Hersh, William H.,Xu, Ping,Simpson, Cheslan K.,Grob, Jonathan,Bickford, Brian,Hamdani, Mohammad Salman,Wood, Thomas,Rheingold, Arnold L.
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- SYNTHESIS OF OPTICALLY PURE ALKYNOLS
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(R,S)-1-alkylprop-2-yn-1-ols have been separated by a 2-step procedure, esterification with N-p-tosyl-(L)-phenylalanine (or valine), recrystallisation of the diastereomeric esters from ethanol/hexane and saponification of the optically pure esters.
- Kuenstler, Th.,Schollmeyer, D.,Singer, H.,Steigerwald, H.
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- Synthesis, characterization and cytotoxicity of mixed-ligand complexes of palladium(II) with 2, 2′-biquinoline/1, 4-diaminobutane and 4-toluenesulfonyl-L-amino acid dianion
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Seven new palladium(II) complexes (1-7) with 4-toluenesulfonyl-L-amino acid dianion and 2, 2′-biquinoline (bqu)/1,4-diaminobutane (dab) have been synthesized and characterized by elemental analysis, IR, 1H NMR, and mass spectra techniques. Crys
- Zhang, Jinchao,Li, Luwei,Ma, Lili,Zhang, Fangfang,Zhang, Zhilei,Wang, Shuxiang
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- Synthesis and Structure-Activity Relationships of Arylsulfonamides as AIMP2-DX2 Inhibitors for the Development of a Novel Anticancer Therapy
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AIMP2-DX2, a splicing variant of AIMP2, is up-regulated in lung cancer, possesses oncogenic activity, and results in tumorigenesis. Specifically inhibiting the interaction between AIMP2-DX2 and HSP70 to suppress AIMP2-DX2-dependent cancers with small molecules is considered a promising avenue for cancer therapeutics. Optimization of hit BC-DXI-04 (IC50 = 40.1 μM) provided new potent sulfonamide based AIMP2-DX2 inhibitors. Among these, BC-DXI-843 showed improved inhibition against AIMP2-DX2 (IC50 = 0.92 μM) with more than 100-fold selectivity over AIMP2 in a luciferase assay. Several binding assays indicated that this compound effectively induces cancer cell apoptosis by specifically interrupting the interaction between DX2 and HSP70, which leads to the degradation of DX2 via Siah1-mediated ubiquitination. More importantly, BC-DXI-843 demonstrated in vivo efficacy in a tumor xenograft mouse model (H460 cells) at a dosage of 50 mg/kg, suggesting it as a promising lead for development of novel therapeutics targeting AIMP2-DX2 in lung cancer.
- Sivaraman, Aneesh,Kim, Dae Gyu,Bhattarai, Deepak,Kim, Minkyoung,Lee, Hwa Young,Lim, Semi,Kong, Jiwon,Goo, Ja-Il,Shim, Seunghwan,Lee, Seungbeom,Suh, Young-Ger,Choi, Yongseok,Kim, Sunghoon,Lee, Kyeong
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p. 5139 - 5158
(2020/05/05)
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- Synthesis and hetero-Diels-Alder reactions of enantiomerically pure dihydro-1: H -azepines
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Thermolysis of enantiomerically pure 3-substituted 7,7-dihalo-2-azabicyclo[4.1.0]heptanes in the presence of K2CO3 gives in good yields 2-alkyl-6-halo-1-tosyl-2,3-dihydro-1H-azepines. These undergo highly stereoselective [4+2] cycloaddition reactions with heterodienophiles and arylation/alkenylation under Suzuki conditions.
- Craig, Donald,Spreadbury, Samuel R. J.,White, Andrew J. P.
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supporting information
p. 9803 - 9806
(2020/09/16)
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- Design and synthesis of tripeptidyl furylketones as selective inhibitors against the β5 subunit of human 20S proteasome
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A series of tripeptidic proteasome inhibitors with furylketone as C-terminus were designed and synthesized. Biochemical evaluations against β1, β2 and β5 subunits revealed that they acted selectively on β5 subunit with IC50s against chymotrypsin-like (CT-L) activity in micromolar range. LC-MS/MS analysis of the ligand-20S proteasome mixture showed that the most potent compound 11m (IC50 = 0.18 μM) made no covalent modification on 20S proteasome. However, it was identified acting in a slowly reversible manner in wash-out assay and the reversibility was much lower than that of MG132, suggesting the possibility of these tripeptidic furylketones forming reversible covalent bonds with 20S proteasome. Several compounds were selected for anti-proliferative assay towards multiple cancer cell lines, and compound 11m displayed comparable potency to positive control (MG132) in all cell lines tested. Furthermore, the pharmacokinetic (PK) data in rats indicated 11m behaved similarly (Cmax, 2007 μg/L; AUC0?t, 680 μg/L·h; Vss, 0.66 L/kg) to the clinical used agent carfilzomib. All these data suggest 11m is a good lead compound to be developed to novel anti-tumor agent.
- Lü, Zirui,Li, Xiaona,Niu, Yan,Sun, Qi,Wang, Chao,Xi, Dandan,Xu, Fengrong,Xu, Ping,Zhou, Tongliang
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- Synthesis, Characterization, and Reactivity of an Ethynyl Benziodoxolone (EBX)-Acetonitrile Complex
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The synthesis of a crystalline ethynyl-1,2-benziodoxol-3(1H)-one (EBX)-acetonitrile complex is described. EBX has been widely used as an active species for a variety of reactions; however, its high instability has so far prevented its isolation. The EBX-acetonitrile is self-assembled into a double-layered honeycomb structure through weak hypervalent iodine secondary interactions and hydrogen bonding. The N-ethynylation of a variety of sulfonamides using the EBX-acetonitrile complex as a substrate under mild conditions is also described.
- Yudasaka, Masaharu,Shimbo, Daisuke,Maruyama, Toshifumi,Tada, Norihiro,Itoh, Akichika
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supporting information
p. 1098 - 1102
(2019/05/16)
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- Iodine-Catalyzed Synthesis of Chiral 4-Imidazolidinones Using α-Amino Acid Derivatives via Dehydrogenative N-H/C(sp3)-H Coupling
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An efficient method for the asymmetric synthesis of 4-imidazolidinones via an iodine-catalyzed intramolecular N-H/C(sp3)-H activation of readily available and abundant feedstocks, amino acids, and amines is described. The reaction proceeded under visible light irradiation to afford a variety of 4-imidazolidinone derivatives under mild conditions in moderate to excellent yields. Secondary and tertiary C(sp3)-H bonds were aminated, and various functional groups were tolerated.
- Kanyiva, Kyalo Stephen,Tane, Marina,Shibata, Takanori
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p. 12773 - 12783
(2019/09/09)
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- Enantioselective vinylation of aldehydes with the vinyl Grignard reagent catalyzed by magnesium complex of chiral BINOLs
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Enantioselective vinylation of aldehydes via direct catalytic asymmetric Grignard reaction of aldehdyes and the vinyl Grinard reagent is a long-standing challenge. This work demonstrated that the magnesium (S)-3,3′-dimethyl BINOLate enantioselectively catalyze the direct vinylation of aldehydes with the deactivated vinylmagnesium bromide by bis(2-[N,N′-dimethylamino]ethyl) ether (BDMAEE) in the addition of n-butylmagnesium chloride. The highest ee of 63% was achieved up to date.
- Wang, Pei,Ma, Guo-Rong,Yu, Sheng-Li,Da, Chao-Shan
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supporting information
p. 79 - 86
(2018/12/13)
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- Synthesis, characterization and in vitro antitrypanosomal activities of new carboxamides bearing quinoline moiety
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The reported toxicities of current antitrypanosomal drugs and the emergence of drug resistant trypanosomes underscore the need for the development of new antitrypanosomal agents. We report herein the synthesis and antitrypanosomal activity of 24 new amide derivatives of 3-aminoquinoline, bearing substituted benzenesulphonamide. Nine of the new derivatives showed comparable antitrypanosomal activities at IC50 range of 1–6 nM (melarsoprol 5 nM). Compound 11n and 11v are more promising antitrypanosomal agents with IC50 1.0 nM than the rest of the reported derivatives. The novel compounds showed satisfactory predicted physico-chemical properties including oral bioavailability, permeability and transport properties.
- Ugwu, David Izuchukwu,Okoro, Uchechukwu Chris,Mishra, Narendra Kumar
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- Metal-Free N–H/C–H Coupling for Efficient Asymmetric Synthesis of Chiral Dihydroquinoxalinones from Readily Available α-Amino Acids
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We have developed a method for the synthesis of dihydroquinoxalinones via intramolecular N–H/C–H coupling using hypervalent iodine. The starting materials were prepared from inexpensive and readily available aniline and amino acid derivatives. Various functional groups were tolerated to give multisubstituted dihydroquinoxalinones in moderate to excellent yields. The chirality of the amino acid was transferred to the desired target compound without a loss of enantiomeric excess. Preliminary mechanistic studies indicated that the reaction proceeds via an ionic mechanism.
- Kanyiva, Kyalo Stephen,Horiuchi, Masashi,Shibata, Takanori
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supporting information
p. 1067 - 1070
(2018/03/06)
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- Synthesis, characterization, molecular docking and in?vitro antimalarial properties of new carboxamides bearing sulphonamide
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Sulphonamides and carboxamides have shown large number of pharmacological properties against different types of diseases among which is malaria. Twenty four new carboxamide derivatives bearing benzenesulphonamoyl alkanamides were synthesized and investigated for their in silico and in?vitro antimalarial and antioxidant properties. The substituted benzenesulphonyl chlorides (1a-c) were treated with various amino acids (2a-h) to obtain the benzenesulphonamoyl alkanamides (3a-x) which were subsequently treated with benzoyl chloride to obtain the N-benzoylated derivatives (5a-f, i-n and q-v). Further reactions of the N-benzoylated derivatives or proline derivatives with 4-aminoacetophenone (6) using boric acid as a catalyst gave the sulphonamide carboxamide derivatives (7a-x) in excellent yields. The in?vitro antimalarial studies showed that all synthesized compounds had antimalarial property. Compound 7k, 7c, 7l, 7s, and 7j had mean MIC value of 0.02, 0.03, 0.05, 0.06 and 0.08?μM respectively comparable with chloroquine 0.06?μM. Compound 7c was the most potent antioxidant agent with IC50 value of 0.045?mM comparable with 0.34?mM for ascorbic acid. In addition to the successful synthesis of the target molecules using boric acid catalysis, the compounds were found to have antimalarial and antioxidant activities comparable with known antimalarial and antioxidant drugs. The class of compounds reported herein have the potential of reducing oxidative stress arising from malaria parasite and chemotherapeutic agent used in the treatment of malaria.
- Ugwu,Okoro,Ukoha,Okafor,Ibezim,Kumar
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p. 349 - 369
(2017/05/04)
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- New carboxamide derivatives bearing benzenesulphonamide as a selective COX-II inhibitor: Design, synthesis and structure-activity relationship
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Sixteen new carboxamide derivatives bearing substituted benzenesulphonamide moiety (7a-p) were synthesized by boric acid mediated amidation of appropriate benzenesulphonamide with 2-amino-4-picoline and tested for anti-inflammatory activity. One compound 7c showed more potent anti-inflammatory activity than celecoxib at 3 h in carrageenan-induced rat paw edema bioassay. Compounds 7g and 7k also showed good anti-inflammatory activity comparable to celecoxib. Compound 7c appeared selectivity index (COX-2/COX-1) better than celecoxib. Compound 7k appeared selectivity index (COX-2/COX-1) a little higher than the half of celecoxib while compound 7g is non-selective for COX-2. The LD50 of compounds 7c, 7g and 7k were comparable to celecoxib.
- Ugwu, David Izuchukwu,Okoro, Uchechukwu Chris,Ahmad, Hilal
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- Synthesis of Six- and Seven-Membered Chloromethyl-Substituted Heterocycles via Palladium-Catalyzed Amino- and Oxychlorination
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The synthesis of six- and seven-membered chloromethyl-substituted heterocycles, such as piperazinone, tetrahydroquinoxaline, benzodiazepinone, and benzoxazepinone, is reported using palladium-catalyzed vicinal diheterofunctionalization of nonactivated alkenes. The reaction conditions for this domino process are soft and mild, and the chloromethyl appendage allows various post-functionalizations via simple nucleophilic substitutions.
- Manick, Anne-Doriane,Berhal, Farouk,Prestat, Guillaume
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supporting information
p. 3719 - 3729
(2016/11/08)
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- PROCESS FOR THE ENANTIOMERIC RESOLUTION OF APREMILAST INTERMEDIATES
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A process for the resolution of racemic 2-(3-ethoxy-4-methoxyphenyl)-1-(methylsulphonyl)-eth-2-ylamine using novel chiral salts is disclosed. An L-phenylalanine p-toluene-sulfonamide salt of (S)-2-(3-ethoxy-4-methoxyphenyl)-1-(methylsulphonyl)-eth-2-ylamine and a di-p-toluoyl-L-tartaric acid salt of (S)-2-(3-ethoxy-4-methoxyphenyl)-1-(methylsulphonyl)-eth-2-ylamine are also provided.
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Page/Page column 12
(2016/11/17)
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- Aqueous MW eco-friendly protocol for amino group protection
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In this paper a new catalyst-free and on-water method for protection of amines and amino acids with di-tert-butyl dicarbonate, 9-fluorenylmethoxycarbonyl chloride, acetyl chloride and tosyl chloride is presented. The protection can be realized in a few minutes under microwave-assistance. The reaction proved to be chemoselective in presence of ambident nucleophiles and water solution of di-tert-butyl carboxylic acid or chloride acid are the only wastes produced.
- Nardi,Cano, N. Herrera,Costanzo,Oliverio,Sindona,Procopio
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p. 18751 - 18760
(2015/06/15)
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- Carbonic anhydrase inhibitors: Design, synthesis, kinetic, docking and molecular dynamics analysis of novel glycine and phenylalanine sulfonamide derivatives
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The inhibition of two human cytosolic carbonic anhydrase isozymes I and II, with some novel glycine and phenylalanine sulfonamide derivatives were investigated. Newly synthesized compounds G1-4 and P1-4 showed effective inhibition profiles with KI values in the range of 14.66-315 μM for hCA I and of 18.31-143.8 μM against hCA II, respectively. In order to investigate the binding mechanisms of these inhibitors, in silico docking studies were applied. Atomistic molecular dynamic simulations were performed for docking poses which utilize to illustrate the inhibition mechanism of used inhibitors into active site of CAII. These sulfonamide containing compounds generally were competitive inhibitors with 4-nitrophenylacetate as substrate. Some investigated compounds here showed effective hCA II inhibitory effects, in the same range as the clinically used sulfonamide, sulfanilamide or mafenide and might be used as leads for generating enzyme inhibitors possibly targeting other CA isoforms which have not been yet assayed for their interactions with such agents.
- Fidan, Ismail,Salmas, Ramin Ekhteiari,Arslan, Mehmet,?entürk, Murat,Durdagi, Serdar,Ekinci, Deniz,?entürk, Esra,Co?gun, Sedat,Supuran, Claudiu T.
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p. 7353 - 7358
(2015/11/27)
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- The effect of hydrogen bond on Br?nsted acid-catalyzed intramolecular hydroamination of unfunctionalized olefins
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The catalytic activity of benzoic acid could be increased by introducing a hydrogen bond donor group at the ortho-position. Preliminary DFT calculation indicated that the activation of CC double bond was realized by the action of both the carboxyl group and the hydrogen bond donor. The amino group was brought to the activated CC bond by the interaction between the carboxyl oxygen and amino proton. This interaction also increased the nucleophilicity of the amino group. Thus, in the presence of 20 mol % of 2-(trifluoromethanesulfonamido)benzoic acid, intramolecular hydroamination of unfunctionalized olefins gave the corresponding products in up to 95% isolated yields.
- Li, Ting-Ting,Liu, Gong-Qing,Wang, Yu-Mei,Cui, Bin,Sun, Hui,Li, Yue-Ming
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supporting information
p. 7003 - 7009
(2015/08/19)
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- Aryl λ3-Iodane-Mediated 6-exo-trig Cyclization to Synthesize Highly Substituted Chiral Morpholines
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A mild and efficient transition metal-free approach has been developed for the synthesis of highly substituted chiral morpholines from alkenols by amino acid-derived iodine(III) reagents via a 6-exo-trig cyclization. The key features of this work include
- Kishorevandavasi, Jaya,Hu, Wan-Ping,Chandrusenadi, Gopal,Chen, Hui-Ting,Chen, Hsing-Yin,Hsieh, Kuang-Chan,Wang, Jeh-Jeng
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supporting information
p. 2788 - 2794
(2015/09/28)
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- Development of amino acid conjugated sulfonamides as potent antiulcer agent
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A series of 2-{[(4-methylphenyl) sulfonyl] amino}-3-sulfanylpropanoic acid (1a) and its analogs 1b-j have been synthesized. These compounds were screened for their in vivo efficacy in pyloric ligation model. Compounds 1a and 1b with higher antiulcer potential were further screened in other gastric models to explore the mode of antiulcer action. To further understand the mode of action, in vitro inhibition of H+/K+ ATPase activity in gastric microsome isolated from rat stomach was studied. This was rationalized by in silico experiments.
- Sahoo, Shakti Prasanna,Subudhi, Bharat Bhusan
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p. 3039 - 3048
(2014/05/06)
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- Oxazoline derivatives tagged with tosylated amino acids as recyclable organocatalysts for enantioselective allylation of aldehydes
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A series of amino acid-based oxazoline compounds have been prepared and successfully applied to the enantioselective allylation reaction of aldehydes. The fine-tuning of the structure of the oxazolines led to (S,S)-4 as an efficient organocatalyst which gave homoallyl alcohols in good yield (up to 90%) and excellent ee (up to 99%) for a wide range of substrates including aromatic, hetero-aromatic and α,β-unsaturated aldehydes. The chiral organocatalyst was synthesized in three easy steps with an overall 88% yield and successfully recycled for up to three cycles. On the basis of the experimental observations and NMR studies, a probable mechanism was proposed for this reaction.
- Ghosh, Debashis,Sadhukhan, Arghya,Maity, Nabin Ch.,Abdi, Sayed H. R.,Khan, Noor-Ul H.,Kureshy, Rukhsana I.,Bajaj, Hari C.
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p. 12257 - 12265
(2014/03/21)
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- Synthesis, characterization, and cytotoxicity of platinum(II)/palladium(II) complexes with 4-toluenesulfonyl-L-amino acid dianion and diimine/diamine
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Eight new platinum(II)/palladium(II) complexes with 4-toluenesulfonyl-L- amino acid dianion and diimine/diamine ligands, [Pd(en)(Tsile)]·H 2O (1), [Pd(bipy)(Tsile)] (2), [Pd(bipy)(Tsthr)]·0.5H 2O (3), [Pd(phen)(Tsile)]·0.5H2O (4), [Pd(phen)(Tsthr)]·H2O (5), [Pd(bqu)(Tsthr)]·1.5H 2O (6), [Pt(en)(Tsser)] (7), and [Pt(en)(Tsphe)]·H 2O (8), have been synthesized and characterized by elemental analyses, 1H NMR and mass spectrometry. The crystal structure of 7 has been determined by X-ray diffraction. Cytotoxicities were tested by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and sulforhodamine B assays. The complexes exert cytotoxicity against HL-60, Bel-7402, BGC-823, and KB cell lines with 4 having the best cytotoxicity against HL-60, Bel-7402, and BGC-823 cell lines; the compounds are less cytotoxic than cisplatin.
- Li, Luwei,Zhang, Jinchao,Ma, Lili,Zhang, Zhilei,Wang, Shuxiang,Li, Shenghui,Zhou, Guoqiang
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p. 638 - 649
(2013/05/22)
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- Synthetically amenable amide derivatives of tosylated-amino acids as organocatalysts for enantioselective allylation of aldehydes: Computational rationale for enantioselectivity
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A phenylalanine derived chiral amide is developed that serves as an effective organocatalyst for the reaction of allyltrichlorosilane with aryl, hetero-aryl and α,β-unsaturated aldehydes to afford the desired homoallylic alcohols in good yield (up to 90%)
- Ghosh, Debashis,Sahu, Debashis,Saravanan,Abdi, Sayed H. R.,Ganguly, Bishwajit,Khan, Noor-Ul H.,Kureshy, Rukhsana I.,Bajaj, Hari C.
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p. 3451 - 3460
(2013/06/05)
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- Oxazoline-based organocatalyst for enantioselective strecker reactions: A protocol for the synthesis of levamisole
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A chiral oxazoline-based or-ganocatalyst has been found to efficiently catalyze asymmetric Strecker reactions of various aromatic and aliphatic N-benzhydrylimines with trime-thylsilyl cyanide (TMSCN) as a cyanide source at -20°C to give α-aminoni-triles in high yield (96%) with excellent chiral induction (up to 98% ee). DFT calculations have been performed to rationalize the enantioselective formation of the product with the organo-catalyst in these reactions. The organo-catalyst has been characterized by single-crystal X-ray diffraction analysis, as well as by other analytical methods. This protocol has been extended to the synthesis of the pharmaceutically important drug molecule levamisole in high yield and with high enantioselectivity.
- Sadhukhan, Arghya,Sahu, Debashis,Ganguly, Bishwajit,Khan, Noor-Ul H.,Kureshy, Rukhsana I.,Abdi, Sayed H.R.,Suresh,Bajaj, Hari C.
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supporting information
p. 14224 - 14232
(2013/11/06)
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- C2-symmetric recyclable organocatalyst for enantioselective Strecker reaction for the synthesis of α-amino acid and chiral diamine-an intermediate for APN inhibitor
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Recyclable chiral amide-based organocatalyst 5 efficiently catalyzed asymmetric Strecker reaction of various aromatic and aliphatic N-benzhydrylimines with ethyl cyanoformate as cyanide source at -10 °C to give a high yield (95%) of α-aminonitriles with excellent chiral induction (ee, up to 99%) with the added advantage of recyclability. Based on experimental observations a probable mechanism was proposed for this reaction. This protocol with catalyst 5 was extended for the synthesis of (R)-phenylalanine and pharmaceutically important drug intermediate (R)-3-phenylpropane-1,2-diamine in high yield with high enantioselectivity.
- Saravanan,Sadhukhan, Arghya,Khan, Noor-Ul H.,Kureshy, Rukhsana I.,Abdi, Sayed H. R.,Bajaj, Hari C.
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experimental part
p. 4375 - 4384
(2012/06/30)
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- Stereoselective synthesis and applications of nitrogen substituted donor-acceptor cyclopropanes (N-DACs) in the divergent synthesis of azacycles
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A new, highly stereoselective intramolecular cyclopropanation of vinylogous carbamates with carbenes in the presence of Cu(acac)2 as the catalyst has been developed for the construction of cyclopropapyrrolidinones. The 'syn' isomer of N-DAC can be converted to the 'anti' isomer by simple silica gel treatment. Regioselective cleavage of each of the cyclopropane bonds of these two acceptor substituted N-DACs led to a diverse array of azacycles.
- Gharpure, Santosh J.,Vijayasree,Reddy, S. Raja Bhushan
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supporting information; scheme or table
p. 1735 - 1738
(2012/04/17)
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- Synthesis, characterization, and biological activity of five new mixed-ligand palladium(II) complexes with ethylenediamine and 4-toluenesulfonyl-L-amino acid dianion
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Five new palladium(II) complexes with 4-toluenesulfonyl-L-amino acid dianion and en, [Pd(en)(TsserNO)] (1), [Pd(en)(TsglyNO)] (2), [Pd(en)(TsalaNO)]·1.5H2O (3), [Pd(en)(TsleuNO)]·H 2O (4), and [Pd(en)(TspheNO)]·2H2O (5), have been synthesized and characterized by elemental analysis, IR, UV, 1H NMR, and mass spectrometry. Crystal structure of 1 has been determined by X-ray diffraction analysis. The cytotoxicity was tested by MTT and SRB assays. The results indicate 1-5 exert cytotoxic effects against HL-60, Bel-7402, BGC-823, and KB cell lines and 5 displays the best cytotoxicity. The structure-activity relationships suggest that both amino acid and N-containing ligands have important effects on cytotoxicity. Copyright
- Zhang, Jinchao,Ma, Lili,Zhang, Fangfang,Zhang, Zhilei,Li, Luwei,Wang, Shuxiang
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experimental part
p. 239 - 250
(2012/06/01)
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- Stereoselective synthesis of morpholines via copper-promoted oxyamination of alkenes
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A new copper(II) 2-ethylhexanoate-promoted addition of an alcohol and an amine across an alkene (oxyamination) is reported. The alcohol addition is intramolecular, while coupling with the amine occurs intermolecularly. Several 2-aminomethyl morpholines we
- Sequeira, Fatima C.,Chemler, Sherry R.
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supporting information
p. 4482 - 4485
(2012/10/29)
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- Synthesis, characterization, and cytotoxicity of complexes of palladium(II) with 1,4-diaminobutane/1,3-diaminopropane and 4-toluenesulfonyl-L-amino acid dianion
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Eight new palladium(II) complexes with 4-toluenesulfonyl-L-amino acid dianion and 1,4-dab/1,3-dap, [Pd(1,4-dab)(TsglyNO)]H2O (1), [Pd(1,4-dab)(TsvalNO)] (2), [Pd(1,4-dab)(TsleuNO)] (3), [Pd(1,4-dab)(TsileNO)] (4), [Pd(1,4-dab)(TsserNO)]0.5H2O (5), [Pd(1,4-dab)(TspheNO)]0. 5H2O (6), [Pd(1,4-dab)(TsthrNO)]H2O (7), and [Pd(1,3-dap)(TsserNO)] (8), have been synthesized and characterized by elemental analysis, IR, UV, 1H NMR, and mass spectrometry. Crystal structure of 8 has been determined by X-ray diffraction. The cytotoxicities were tested by MTT assay. The results indicate the complexes exert cytotoxic effects against HL-60 and Bel-7402. The structure-activity relationship suggests that both amino acids and N-containing ligands have important effects on cytotoxicity, but the IC50 values do not show definite correlation with variation of these ligands.
- Ma, Lili,Zhang, Jinchao,Zhang, Fangfang,Chen, Chao,Li, Luwei,Wang, Shuxiang,Li, Shenghui
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p. 3160 - 3173
(2012/10/30)
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- A modified synthetic approach to optically pure benzoxazepines from amino acid precursors using intramolecular buchwald-hartwig C-O bond-formation reaction
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Palladium-catalyzed intramolecular aryl etherification reaction using bulky binaphthylphosphane ligand is shown to be a convenient method for the synthesis of seven-membered heterocycles. Application of this methodology to a naturally occurring proteinoge
- Bhattacharya, Debleena,Behera, Ashok,Hota, Sandip K.,Chattopadhyay, Partha
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scheme or table
p. 585 - 592
(2011/04/12)
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- Diversity-oriented synthesis based on the dppp-catalyzed mixed double-michael reactions of electron-deficient acetylenes and β-amino alcohols
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In this study, we prepared oxizolidines through 1,3-bis(diphenylphosphino)- propane (DPPP)-catalyzed mixed double-Michael reactions of β-amino alcohols with electron-deficient acetylenes. These reactions are very suitable for the diversity-oriented parallel syntheses of oxizolidines because: (i) they are performed under mild metal-free conditions and (ii) the products are isolated without complicated work-up. To demonstrate the applicability of mixed double-Michael reactions for the preparation of five-membered-ring heterocycles, we prepared 60 distinct oxazolidines from five β-amino alcohols and 12 electron-deficient acetylenes. We synthesized 36 of these 60 oxazolidines in enantiomerically pure form from proteinogenic amino acid-derived β-amino alcohols.
- Fan, Yi Chiao,Kwon, Ohyun
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scheme or table
p. 3802 - 3825
(2011/06/24)
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- Modular amino acids-based chiral ligands for copper-catalyzed enantioselective conjugation addition of diethylzinc to cyclic enones
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New amino acid-based modular chiral ligands were readily synthesized and used to catalyze the asymmetric conjugate addition of Et2Zn to various cyclic enones in the presence of a variety of copper sources. Moderately high ee of up to 72% were o
- Gou, Shaohua,Judeh, Zaher M. A.
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scheme or table
p. 105 - 112
(2011/11/04)
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- Synthesis, characterization, and cytotoxicity of mixed-ligand complexes of platinum(II) with 2,2′-bipyridine and 4-toluenesulfonyl-L-amino acid dianion
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Five new platinum(II) complexes (1-5) with 4-toluenesulfonyl-L-amino acid dianion and 2,2′-bipyridine (bipy) have been synthesized and characterized by elemental analysis, IR, UV, 1H-NMR, 13C-NMR, and mass spectra. The crystal structure of 1 has been determined by X-ray diffraction analysis. Cytotoxicity was tested by 3-(4,5-dimethylthiazol-2-yl)-2,5- diphenyltetrazolium bromide (MTT) and sulforhodamine B (SRB) assays. The results indicate that 1-5 exert cytotoxic effects with selectivity against tested carcinoma cell lines; 5 displays better cytotoxicity against BGC-823, Bel-7402, and KB cell lines, while 1 has better cytotoxicity against KB cell line. The 4-toluenesulfonyl- L-amino acid dianions have important effects on cytotoxicity; when 4-toluenesulfonyl-L-amino acid dianions are 4-toluenesulfonyl-L-glycine and 4-toluenesulfonyl-L-phenylalanine, the complexes show better cytotoxicity.
- Zhang, Jin Chao,Li, Luwei,Ma, Lili,Zhang, Fangfang,Wang, Shuxiang
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experimental part
p. 1695 - 1706
(2012/02/01)
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- Copper(II) triflate-catalyzed intramolecular hydroamination of homoallylic amino alcohols as an expedient route to trans-2,5-dihydro-1H-pyrroles and 1,2-dihydroquinolines
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A new efficient synthetic route to trans-2,5-dihydro-1H-pyrroles and 1,2-dihydroquinolines that relies on copper(II) triflate-catalyzed intramolecular hydroamination of homoallylic amino alcohols under mild and operationally straightforward conditions is
- Rao, Weidong,Kothandaraman, Prasath,Koh, Chii Boon,Chan, Philip Wai Hong
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supporting information; experimental part
p. 2521 - 2530
(2011/02/21)
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- Facile preparation of N-Tosyl-L-Phenylalanine chloromethyl ketone
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A method for the facile preparation of N-tosyl-L- phenylalanine chloromethyl ketone was developed. L- Phenylalanine was tosylated and converted to the activated ester of p-nitrophenol. Subsequent reaction with dimethylsulfoxonium methylide and treatment with lithium chloride and methanesulfonic acid afforded the α-chloroketone.This practical procedure avoided the use of toxic and explosive diazomethane.
- Gao, Bing-Lei,Ma, Shu-Tao,Liu, Zhao-Peng
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scheme or table
p. 648 - 649
(2010/06/13)
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- Practical synthetic process for enantiopure 1-benzyl-3-hydroxypyrrolidine
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The synthesis of (S)-1-benzyl-3-hydroxypyrrolidine (S)-5 comprised the asymmetric hydroboration of 1-benzyl-3-pyrroline 4, followed by oxidation and chiral purification via diastereomeric salt formation. The asymmetric borane reagent was generated 'in situ' from NaBH4, BF3-OEt2, and (+)-α-pinene 1 (85% ee) and reacted with 4, prepared from cis-1,4-butenediol 3, to give crude product (S)-5. The following chiral purification via diastereomeric salt formation proceeded to afford (S)-5 with >99% ee. The optimized process was successfully scaled up to an industrial scale to produce a 252 kg batch of (S)-5.
- Morimoto, Masao,Sakai, Kenichi
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p. 1464 - 1468
(2008/12/20)
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- β-cyclodextrin-catalyzed monosulfonylation of amines and amino acids in water
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A mild and efficient procedure has been developed for the first time under biomimetic conditions for the monosulfonylation of various amines and amino acids catalyzed by β-cyclodextrin in water at room temperature to afford the corresponding sulfonamides in high yields.
- Sridhar,Srinivas,Kumar, V. Pavan,Narender,Rao, K. Rama
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p. 1873 - 1876
(2008/09/16)
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- Asymmetric addition of phenylacetylene to aldehydes catalyzed by β-sulfonamide alcohol-titanium complex
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A series of β-sulfonamide alcohol ligands were synthesized from L-phenylalanine. Titanium complexes of these compounds were used to catalyze the asymmetric addition of phenylacetylene to a number of aldehydes. When the conditions were optimized, 20 mol % of ligand 8a catalyzed the reaction with high enantioselectivity (up to 98% ee) and good yield (up to 92%). When a small amount of MeOH was added to the reaction as a modifier, as little as 5 mol % of ligand was required to efficiently catalyze the reaction under very mild conditions, resulting in an ee of up to 99% and good yield.
- Xu, Zhaoqing,Lin, Li,Xu, Jiangke,Yan, Wenjin,Wang, Rui
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p. 506 - 514
(2007/10/03)
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- Synthesis of α-amino acids by reaction of aziridine-2-carboxylic acids with carbon nucleophiles
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A variety of homochiral α-amino acids have been prepared in good yield via regioselective reaction of higher order cuprates with (2S)-N-para-toluenesulfonylaziridine-2-carboxylic acid 4. The reaction was much less regioselective and low yielding when higher order cuprates were reacted with the more hindered aziridine carboxylic acid 30, the principal products being protected β-amino acids. Reaction of lithium trimethylsilylacetylide with the aziridine acid 30, however, gave a protected α-amino acid which was converted to the protected isoleucine ester 37. The Royal Society of Chemistry 2006.
- Beresford, Kenneth J. M.,Church, Nicola J.,Young, Douglas W.
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p. 2888 - 2897
(2008/02/08)
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- Oxobenzo[f]benzopyrans as new fluorescent photolabile protecting groups for the carboxylic function
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The properties of three oxobenzo[f]benzopyrans as new fluorogenic photolabile protecting groups for the carboxylic function of?amino acids were studied. Fluorescent amino acid conjugates were efficiently prepared and characterised. Photodeprotection of these compounds was carried out by irradiation at 300, 350 and 419 nm, the most suitable wavelength being 350 nm, on account of short irradiation times and good deprotection yields.
- Piloto, Ana M.,Rovira, Daniel,Costa, Susana P.G.,Gon?alves, M. Sameiro T.
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p. 11955 - 11962
(2007/10/03)
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- Simple derivatives of natural amino acids as chiral ligands in the catalytic asymmetric addition of phenylacetylene to aldehydes
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Optically active propargylic alcohols are important chiral building blocks in asymmetric synthesis, and asymmetric addition of terminal alkynes to aldehydes is one of the most important and interesting procedures by which to prepare these chiral building
- Han, Zhi-Jian,Wang, Rui,Zhou, Yi-Feng,Liu, Lei
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p. 934 - 938
(2007/10/03)
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- Amino acid-derived hydroxamic acids as chiral ligands in the vanadium catalysed epoxidation
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New sulfonamide-derived hydroxamic acids 7-11 have been developed as chiral ligands for the V-catalysed asymmetric epoxidation, showing high reactivity at subzero temperatures and moderate to good enantioselectivity. The strong accelerating effect exhibited by the ligands of this type can be attributed to the sulfonamide functionality. A range of cinnamyl type allylic alcohols were epoxidised with up to 74% ee. The Royal Society of Chemistry 2005.
- Malkov, Andrei V.,Bourhani, Zainaba,Kocovsky, Pavel
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p. 3194 - 3200
(2007/10/03)
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- Synthesis and structure of lower rim C-linked N-tosyl peptidocalix[4]arenes
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Chiral p-tert-butylcalix[4]arenes functionalized at the lower rim with amino acid residues have been prepared. The 1H and 13C NMR spectra indicate that the macrocycles preferably adopt a cone conformation. Calix[4]arenes bearing amin
- Sdira, Sofiane Ben,Felix, Caroline P.,Giudicelli, Marie-Beatrice A.,Seigle-Ferrand, Pascal F.,Perrin, Monique,Lamartine, Roger J.
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p. 6632 - 6638
(2007/10/03)
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- Highly Enantioselective Addition of Phenylacetylene to Aldehydes Catalyzed by a β-Sulfonamide Alcohol-Titanium Complex
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Three simple steps were required to prepare the β-sulfonamide alcohol ligand (L*) from L-phenylalanine. Its titanium complex efficiently catalyzes the asymmetric addition of phenylacetylene (2) to aromatic aldehydes 1 to form enantiomerically pure proparg
- Xu, Zhaoqing,Wang, Rui,Xu, Jiangke,Da, Chao-Shan,Yan, Wen-Jin,Chen, Chao
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p. 5747 - 5749
(2007/10/03)
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- A new convenient approach to chiral β-aryl(heteroaryl)alkylamines
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Chiral β-aryl(heteroaryl)alkylamines have been prepared from N-tosyl alkylaziridines via regiospecific nucleophilic ring opening and subsequent desulfonylation in good to excellent yields. The corresponding aziridines are easily obtained from commercially available (S)-α-amino acids, so this method is the first effective route to asymmetric β-aryl(heteroaryl)alkylamines.
- Nenajdenko, Valentine G,Karpov, Alexei S,Balenkova, Elizabeth S
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p. 2517 - 2527
(2007/10/03)
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- Enantioselective addition of diethylzinc to aldehydes catalyzed by titanium(IV) complexes of N-sulfonylated amino alcohols with two stereogenic centers
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Bidentate N-sulfonylated amino alcohols with one or two stereogenic centers were prepared and applied as chiral ligands in the titanium(IV)-catalyzed asymmetric addition of diethylzinc to aldehydes, affording excellent enantioselectivities of up to 98% e.e.
- You, Jing-Song,Shao, Ming-Yuan,Gau, Han-Mou
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p. 2971 - 2975
(2007/10/03)
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- Chiral aryl sulfonyl hydantoins as hypoglycemic agents
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Some novel chiral sulfonyl hydantoin derivatives 2a-e and 3a-e have been prepared. p-Toluenesulfonyl chloride on treatment with L-amino acids in presence of K2CO3/H2O yielded N-(p-toluensulfonyl-)amino acids 1a-e which were cyclized in presence of NH4SCN / Ac2O to afford 1-(p-toluenesulfonyl)-5-substituted-2-thiohydantoins 2a-e. These compounds were oxidized with HNO3 to yield 1-(p-toluenesulfonyl)-5-substituted hydantoins 3a-e. The enantiomeric ratios of 3a-e were determined by 1H NMR spectroscopy using Eu(hfc)3. The antidiabetic activity of 3a-d has been determined.
- Ahmad, Roshan,Jabeen, Rukhsana,Zia-Ul-Haq, Mohammad,Nadeem, Humaira,Duddeck, Helmut,Verspohl, Eugen J.
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p. 203 - 207
(2007/10/03)
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- Deprotection of sulfonyl aziridines
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The deprotection of the chiral N-sulfonyl aziridines 1-3 has been studied under different desulfonylation conditions. Two methods for the efficient aleprotection of 2-benzyl-, 2-phenyl-, and 2-carboxyl-N- sulfonylaziridines were found. The desulfonylation with lithium and a catalytic amount of di-tert-butyl biphenyl in THF at -78 °C led to the corresponding NH aziridines with yields up to 85%. Alternatively, the desulfonylation could be carried out with magnesium in methanol under ultrasonic conditions. The latter proved to be a very mild method and afforded the desulfonylated aziridines with yields up to 75%, even when the 2-phenyl substituted aziridine 2 was the studied substrate. Furthermore, in all the cases studied, no racemization was observed in the chiral center of the aziridines.
- Alonso, Diego A.,Andersson, Pher G.
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p. 9455 - 9461
(2007/10/03)
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