- Design, Synthesis, and Antifungal Activity of 2,6-Dimethyl-4-aminopyrimidine Hydrazones as PDHc-E1 Inhibitors with a Novel Binding Mode
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A series of novel 2,6-dimethyl-4-aminopyrimidine hydrazones 5 were rationally designed and synthesized as pyruvate dehydrogenase complex E1 (PDHc-E1) inhibitors. Compounds 5 strongly inhibited Escherichia coli (E. coli) PDHc-E1 (IC50 values 0.94-15.80 μM). As revealed by molecular docking, site-directed mutagenesis, enzymatic, and inhibition kinetic analyses, compounds 5 competitively inhibited PDHc-E1 and bound in a "straight"pattern at the E. coli PDHc-E1 active site, which is a new binding mode. In in vitro antifungal assays, most compounds 5 at 50 μg/mL showed more than 80% inhibition against the mycelial growth of six tested phytopathogenic fungi, including Botrytis cinerea, Monilia fructigena, Colletotrichum gloeosporioides, andBotryosphaeria dothidea. Notably, 5f and 5i were 1.8-380 fold more potent against M. fructigena than the commercial fungicides captan and chlorothalonil. In vivo, 5f and 5i controlled the growth of M. fructigena comparably to the commercial fungicide tebuconazole. Thus, 5f and 5i have potential commercial value for the control of peach brown rot caused by M. fructigena.
- Zhou, Yuan,Zhang, Shasha,Cai, Meng,Wang, Kaixing,Feng, Jiangtao,Xie, Dan,Feng, Lingling,Peng, Hao,He, Hongwu
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p. 5804 - 5817
(2021/06/25)
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- Allylic and Allenylic Dearomatization of Indoles Promoted by Graphene Oxide by Covalent Grafting Activation Mode
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The site-selective allylative and allenylative dearomatization of indoles with alcohols was performed under carbocatalytic regime in the presence of graphene oxide (GO, 10 wt percent loading) as the promoter. Metal-free conditions, absence of stoichiometric additive, environmentally friendly conditions (H2O/CH3CN, 55 °C, 6 h), broad substrate scope (33 examples, yield up to 92 percent) and excellent site- and stereoselectivity characterize the present methodology. Moreover, a covalent activation model exerted by GO functionalities was corroborated by spectroscopic, experimental and computational evidences. Recovering and regeneration of the GO catalyst through simple acidic treatment was also documented.
- Lombardi, Lorenzo,Bellini, Daniele,Bottoni, Andrea,Calvaresi, Matteo,Monari, Magda,Kovtun, Alessandro,Palermo, Vincenzo,Melucci, Manuela,Bandini, Marco
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supporting information
p. 10427 - 10432
(2020/07/24)
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- Design, synthesis and biological evaluation of tryptamine salicylic acid derivatives as potential antitumor agents
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A series of tryptamine salicylic acid derivatives were synthesized and their antiproliferative activity against MGC-803, MCF-7, HepG2, A549 and HeLa cell lines was evaluated. The structure-activity relationship (SAR) study revealed that different substitutions of the C5 and C3′-C5′ positions have certain effects on the anti-proliferation activity. The growth assay revealed that N-[2-(5-bromo-1H-indol-3-yl)-ethyl]-2-hydroxy-3-methyl-benzamide (E20) showed the most potent and broad-spectrum anticancer inhibition of all the cell lines evaluated, and was only more potent than 5-Fu for the gastric cancer cell line. Preliminary studies indicated that compound E20 could inhibit colony formation and migration of MGC-803 cells. The flow cytometry (FCM) results showed that compound E20 arrested the cell cycle in the G2/M phase and induced apoptosis of MGC-803 cells in a concentration-dependent manner. In addition, the western blot results showed that E20 can down-regulate the expression of hexokinase 2. Our studies suggest that the framework of N-[2-(5-bromo-1H-indol-3-yl)-ethyl]-2-hydroxy-3-methyl-benzamide may be consider as a new type of chemical for designing effective anti-cancer drugs targeting gastric cancer cells.
- Xiong, Runde,He, Dongxiu,Deng, Xiangping,Liu, Juan,Lei, Xiaoyong,Xie, Zhizhong,Cao, Xuan,Chen, Yanming,Peng, Junmei,Tang, Guotao
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p. 573 - 583
(2019/04/30)
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- Discovery of 1,3,4-oxadiazol-2-one-containing benzamide derivatives targeting FtsZ as highly potent agents of killing a variety of MDR bacteria strains
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The spread of infections caused by multidrug-resistant (MDR) pathogens, such as methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant S. aureus (VRSA), has created a need for new antibiotics with novel mechanisms of action. The bacterial division protein FtsZ has been identified as a novel drug target that can be exploited clinically. As part of an ongoing effort to develop FtsZ-targeting antibacterial agents, we describe herein the design, synthesis and bioactivity of six series of novel 1,3,4-oxadiazol-2-one-containing, 1,2,4-triazol-3-one-containing and pyrazolin-5-one-containing benzamide derivatives. Among them, compound A14 was found to be the most potent antibacterial agent, much better than clinical drugs such as ciprofloxacin, linezolid and erythromycin against all the tested gram-positive strains, particularly methicillin-resistant, penicillin-resistant and clinical isolated S. aureus. Subsequent studies on biological activities and docking analyses proved that A14 functioned as an effective compound targeting FtsZ. Preliminary SAR indicated a general direction for further optimization of these novel analogues. Taken together, this research provides a promising chemotype for developing newer FtsZ-targeting bactericidal agents.
- Bi, Fangchao,Song, Di,Qin, Yinhui,Liu, Xingbang,Teng, Yuetai,Zhang, Na,Zhang, Panpan,Zhang, Nan,Ma, Shutao
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p. 3179 - 3193
(2019/06/17)
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- Preparation method of 4-methyl phenylhydrazine hydrochloride
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The invention relates to a preparation method of 4-methyl phenylhydrazine hydrochloride. The preparation method comprises the following steps: diazotization, reduction, purification and salt formation. In the diazotization and reduction steps, reaction liquid is kept with high acidity by means of concentrated hydrochloric acid, so that the reaction is smoothly and fully carried out. In the reduction step, zinc powder-concentrated hydrochloric acid is taken as a reducing agent to replace sodium thiosulfate, sodium hydrogen sulfite, stannous chloride-hydrochloric and the like, the reducing property is good, the yield is high, the reaction time is shortened, impurities such as zinc hydroxide generated by the reaction are conveniently removed, and the product is few in impurity and high in purity. In the salt formation step, acetone is used to wash, so that the purity of the product is improved, and the appearance of the product is ensured. According to the preparation method, the processis stable and reliable, the operation is easy, the product purity is high (the content of the product detected by high performance liquid chromatography is greater than or equal to 99%), the yield isgreater than or equal to 39%, and the demand on 4-methyl phenylhydrazine hydrochloride in the market is fully met.
- -
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Paragraph 0017; 0025; 0026; 0036; 0046
(2018/07/30)
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- Synthesis of Aryl Hydrazines via CuI/BMPO Catalyzed Cross-Coupling of Aryl Halides with Hydrazine Hydrate in Water
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The N,N’-bis(2,6-dimethylphenyl)oxalamide was discovered as a powerful ligand for Cu-catalyzed cross-coupling of aryl halides with hydrazine hydrate, leading to the formation of a variety of aryl hydrazines at 80 oC in water under the assistance of K3PO4 and 4 mol% cetyltrimethylammonium bromide from aryl bromides and aryl iodides. Good to excellent yields were observed in most cases.
- Kumar, Siripuram Vijay,Ma, Dawei
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supporting information
p. 1003 - 1006
(2018/09/20)
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- Indole amide compound with antitumor activity for treating cancer
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The invention discloses an indole amide compound with antitumor activity, which can be used for treating various types of cancer. Therefore, the indole amide compound can be used as a lead compound for antitumor drugs, and has good development and application prospects.
- -
-
Paragraph 0021
(2018/10/27)
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- Design, synthesis and biological evaluation of glutamic acid derivatives as anti-oxidant and anti-inflammatory agents
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A series of glutamic acid derivatives was synthesized and evaluated for their antioxidant activity and stability. We found several potent and stable glutamic acid derivatives. Among them, compound 12b exhibited good in vitro activity, chemical stability and cytotoxicity. A prototype compound 12b showed an anti-inflammatory effect in LPS-stimulated RAW 264.7 cell lines and in a zebrafish model.
- Pagire, Suvarna H.,Lee, Eunhye,Pagire, Haushabhau S.,Bae, Eun Jung,Ryu, Soo Jung,Lee, Dahye,Kim, Min Hee,Kim, Geum Ran,Hwang, Kyu-Seok,Ahn, Sukyung,Maeng, Jin Hee,Song, Jin Sook,Bae, Myung Ae,Lee, Don Hang,Ahn, Jin Hee
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p. 529 - 532
(2018/01/04)
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- Synthesis, in vitro Antimicrobial, and Cytotoxic Activities of New 1,3,4-Oxadiazin-5(6H)-one Derivatives from Dehydroabietic Acid
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A series of new 1,3,4-oxadiazin-5(6H)-one derivatives (6a–n) of dehydroabietic acid were designed and synthesized as potential antimicrobial and antitumor agents. Their structures were characterized by IR, 1H NMR, 13C NMR, MS, and elemental analyses. All the title compounds were evaluated for their antimicrobial activity against four bacterial and three fungal strains using the serial dilution method. Among them, compound 6e showed the highest antibacterial activity against Bacillus subtilis with a minimum inhibitory concentration (MIC) value of 1.9 μg/mL. In addition, the in vitro cytotoxic activities of the title compounds were also assayed against three human carcinoma cell lines (MCF-7, SMMC-7721, and HeLa) through the MTT colorimetric method. As a result, compounds 6b, 6g, 6k, and 6m exhibited significant inhibition against at least one cell line with IC50 values below 10 μM. Compound 6m was especially found to be the most potent derivative with IC50 values of 2.26 ± 0.23, 0.97 ± 0.11, and 1.89 ± 0.31 μM against MCF-7, SMMC-7721, and HeLa cells, respectively, comparable to positive control etoposide.
- Jin, Xiao-Yan,Zhang, Kang-Ping,Chen, Hao,Miao, Ting-Ting,Wang, Shi-Fa,Gu, Wen
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p. 538 - 547
(2018/06/11)
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- Synthesis and biological evaluation of (1-aryl-1H-pyrazol-4-yl) (3,4,5-trimethoxyphenyl)methanone derivatives as tubulin inhibitors
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A series of (1-aryl-1H-pyrazol-4-yl) (3,4,5-trimethoxyphenyl)methanones (8a-p, 9a-p) and ketoxime (10c) derivatives were designed and synthesized as antitubulin agents. All of the target compounds were evaluated for the in vitro anti-proliferative activities against three tumor cell lines (A549, HT-1080, SGC-7901). The most promising compounds in this class were (1-(p-tolyl)-1H-pyrazol-4-yl) (3,4,5-trimethoxyphenyl)methanone (9c) and its ketoxime derivative (10c), which significantly inhibited tumor cells growth with IC50 value of 0.054–0.16 μM. Meanwhile, compound 9c exhibited effectively inhibitory activity of tubulin polymerization. Consistent with its antitubulin activity, compound 9c could destructively damage microtubule network and arrest SGC-7901 cell cycle at G2/M phase significantly. The structure-activity relationship (SAR) and conformational analysis indicate that methyl group at C4-position of C-ring is critical for the activities and the amino group at the C5-position of B-ring plays a negative role in maintaining bioactivity. Furthermore, a molecular docking study was performed to elucidate its binding mode at the colchicine site in the tubulin heterodimer.
- Zhai, Min'an,Wang, Long,Liu, Shiyuan,Wang, Lijing,Yan, Peng,Wang, Junfang,Zhang, Jingbo,Guo, Haifei,Guan, Qi,Bao, Kai,Wu, Yingliang,Zhang, Weige
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p. 137 - 147
(2018/07/13)
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- Rh(II)-catalyzed intramolecular annulation of N-sulfonyl 1,2,3-triazoles with indole derivatives: A new method for synthesis pyranoindoles
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A direct and highly stereoselective approach for the synthesis of Z-alkenyl-pyranoindoles had been developed by utilizing Rh(II)-catalyzed intramolecular cyclization of N-sulfonyl-1,2,3-triazoles with indole derivatives. A variety of pyranoindoles were obtained in 44-93% yields. Moreover, a more convenient synthesis of pyranoindoles starting from terminal alkyne was realized via a Cu-Rh sequentially catalyzed one-pot cascade reaction.
- Xie, Hui,Yang, Jian-Xin,Bora, Pranjal Protim,Kang, Qiang
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supporting information
p. 3014 - 3021
(2016/05/19)
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- A diversity-oriented approach to indolocarbazoles: Via Fischer indolization and olefin metathesis: Total synthesis of tjipanazole D and i
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New synthetic strategies to indolocarbazoles have been reported via two-fold Fischer indolization under green conditions using l-(+)-tartaric acid and N,N-dimethyl urea. Starting with cyclohexanone, a bench-top starting material, this methodology has been extended to the total synthesis of natural products such as tjipanazoles D and I as well as the core structure of asteropusazole and racemosin B. Here, atom economical reactions like ring-closing metathesis, enyne-metathesis, and the Diels-Alder reaction have been used as key steps. Diverse strategies demonstrated here are useful in medicinal chemistry and materials science to design a library of decorated indoles.
- Kotha, Sambasivarao,Saifuddin, Mohammad,Aswar, Vikas R.
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supporting information
p. 9868 - 9873
(2016/10/31)
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- Rhodium(III)-catalyzed in situ oxidizing directing group- assisted c-h bond activation and olefination: A route to 2-vinylanilines
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A new and efficient method for the synthesis of 2-vinylanilines from the reaction of arylhydrazine hydrochlorides with alkenes and diethyl ketone via a rhodium-catalyzed C-H activation is described. The oxidant-free olefination reaction involves the in situ generation of an -N-N=CR1R2 moiety as the oxidizing directing group thus providing an easy access to 2-vinylanilines.
- Muralirajan, Krishnamoorthy,Haridharan, Radhakrishnan,Prakash, Sekar,Cheng, Chien-Hong
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supporting information
p. 761 - 766
(2015/03/18)
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- Synthesis and biological evaluation of 3-alkyl-1,5-diaryl-1H-pyrazoles as rigid analogues of combretastatin A-4 with potent antiproliferative activity
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A series of novel 3-alkyl-1,5-diaryl-1H-pyrazoles were synthesized as combretastatin A-4 (CA-4) analogues and evaluated for antiproliferative activity against three human cancer cell lines (SGC-7901, A549 and HT-1080). Most of the target compounds displayed moderate to potent antiproliferative activity, and 7k was found to be the most potent compound. Structure-activity relationships indicated that compounds with a trimethoxyphenyl A-ring at the N-1 position of the pyrazole skeleton were more potent than those with the A-ring at the C-5 position. Tubulin polymerization and immunostaining experiments revealed that 7k potently inhibited tubulin polymerization and disrupted tubulin microtubule dynamics in a manner similar to CA-4. Computational modelling demonstrated that the binding of 7k to the colchicine binding site on microtubules may involve a similar mode as CA-4.
- Xu, Qile,Qi, Huan,Sun, Maolin,Zuo, Daiying,Jiang, Xuewei,Wen, Zhiyong,Wang, Zhiwei,Wu, Yingliang,Zhang, Weige
-
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- Nickel-catalyzed N-arylation of benzophenone hydrazone with bromoarenes
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A nickel-catalyzed method for the cross-coupling of benzophenone hydrazone with aryl bromides is described. The use of a simple Ni(ii)/NHC catalyst leads to the arylated hydrazones in good or acceptable yields. This protocol provides a simple, convenient alternative to the synthesis of arylhydrazines.
- Wu, Wei,Fan, Xin-Heng,Zhang, Li-Peng,Yang, Lian-Ming
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p. 3364 - 3367
(2014/01/06)
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- Facile and convenient synthesis of aryl hydrazines via copper-catalyzed C-N cross-coupling of aryl halides and hydrazine hydrate
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An efficient and convenient method for the synthesis of aryl hydrazines has been developed via copper-catalyzed cross-coupling of aryl bromides and hydrazine with a readily accessible ligand and water as a solvent. The multigram scale procedure is applicable to aryl bromides bearing both moderately electron-donating and electron-withdrawing substituents in the aromatic nucleus. No column chromatography is required to obtain aryl hydrazine hydrochlorides in good yields.
- Kurandina, Daria V.,Eliseenkov, Eugene V.,Ilyin, Petr V.,Boyarskiy, Vadim P.
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p. 4043 - 4048
(2014/06/09)
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- Design, synthesis, crystal structures, and insecticidal activities of eight-membered azabridge neonicotinoid analogues
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Three series of novel azabridge neonicotinoid analogues were designed and synthesized, which were constructed by starting material A, glutaraldehyde, and primary amine hydrochlorides (aliphatic amines, phenylhydrazines, and anilines). Most of the eight-membered azabridge compounds presented higher insecticidal activities than oxabridged compound B against cowpea aphid (Aphis craccivora) and brown planthopper (Nilaparvata lugens). Compared with imidacloprid, some azabridged compounds exhibited excellent insecticidal activity against brown planthopper. The crystal structures and bioassay indicated that changing bridge atoms from O to N could lead to entirely different conformations, which might be the important influential factor of the bioactivities.
- Xu, Renbo,Xia, Rui,Luo, Ming,Xu, Xiaoyong,Cheng, Jiagao,Shao, Xusheng,Li, Zhong
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p. 381 - 390
(2014/02/14)
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- Regioselective synthesis of indoles via rhodium-catalyzed C-H activation directed by an in-situ generated redox-neutral group
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A regioselective synthesis of indoles from arylhydrazine hydrochlorides with alkynes and diethyl ketone catalyzed by a rhodium complex is described. A possible mechanism involving an in-situ generated oxidizing directing group -N-Ni'CR1R2 assisted ortho-C-H activation and reductive elimination are proposed. The catalytic reaction is highly compatible with a wide range of functional arylhydrazines and alkynes. The reaction proceeds under mild reaction conditions and is atom-step economical.
- Muralirajan, Krishnamoorthy,Cheng, Chien-Hong
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p. 1571 - 1576
(2014/06/09)
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- Indole synthesis by rhodium(III)-catalyzed hydrazine-directed C-H activation: Redox-neutral and traceless by N-N bond cleavage
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Fishing for complements! There is an alternative to the useful Fischer indole synthesis. The new method utilizes the same retrosynthetic disconnection but is based on a RhIII-catalyzed directed C-H activation step and a successive coupling with alkynes. Copyright
- Zhao, Dongbing,Shi, Zhuangzhi,Glorius, Frank
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supporting information
p. 12426 - 12429
(2013/12/04)
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- Design and synthesis of antifungal benzoheterocyclic derivatives by scaffold hopping
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The incidence of invasive fungal infections and associated mortality is increasing dramatically. Although azoles are first-line antifungal agents, cross-resistance and hepatic toxicity are their two major limitations. The discovery of novel non-azole lead compounds will be helpful to overcome these problems. On the basis of our previously reported benzopyran non-azole CYP51 inhibitor, scaffold hopping was used to design structurally diverse new compounds and expand the structure-activity relationships of the lead structure. Five kinds of scaffolds, namely benzimidazole, benzoxazole, benzothiazole, quinazolin-4-one and carboline, were chosen for synthesis. In vitro antifungal activity data and results from molecular docking revealed that the scaffold was important for the antifungal activity. Several compounds showed potent activity against both standard and clinically resistant fungal pathogens, suggesting that they can serve as a good starting point for the discovery of novel antifungal agents.
- Sheng, Chunquan,Che, Xiaoying,Wang, Wenya,Wang, Shengzheng,Cao, Yongbing,Yao, Jianzhong,Miao, Zhenyuan,Zhang, Wannian
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scheme or table
p. 1706 - 1712
(2011/05/06)
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- Copper-mediated synthesis of substituted 2-aryl-N-benzylbenzimidazoles and 2-arylbenzoxazoles via C-H functionalization/C-N/C-O bond formation
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An efficient method for the transformation of N-benzyl bisarylhydrazones and bisaryloxime ethers to functionalized 2-aryl-N-benzylbenzimidazoles and 2-arylbenzoxazoles is described. The protocol involves a copper(II)-mediated cascade C-H functionalization/C-N/C-O bond formation under neutral conditions. Substrates having either electron-donating or -withdrawing substituents undergo the cyclization to afford the target heterocycles at moderate temperature.
- Guru, Murali Mohan,Ali, Md Ashif,Punniyamurthy, Tharmalingam
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scheme or table
p. 5295 - 5308
(2011/08/05)
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- INDICYANINE DYES AND THE DERIVATIVES THEREOF FOR ANALYSING BIOLOGICAL MICROMOLECULES
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The invention relates to two series of synthesised indolenine pentamethine dyes (37 compounds) comprising a reactive group in the third and fifth positions of the indolenine cycle, respectively. A method for producing, extracting and purifying the dyes and the precursors thereof, consisting in determining the absorption and fluorescence maxima, molecular extinction factors, fluorescence quantum yields, relative fluorescence effectiveness at excitation on a wavelength of 635 nm (detection of 670 nm) and 655 nm (detection of 690 nm), relative light stability and comparative sensitivity of detection of marked oligonucleotides on biochips of the claimed dyes, is disclosed. The use of the claimed dyes in the form of fluorescent marks for oligonucleotide and protein chips is also disclosed.
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Page/Page column 41-42
(2010/04/23)
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- Synthesis and antimicrobial activities of novel 1H-dibenzo[a,c]carbazoles from dehydroabietic acid
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A series of novel 1H-dibenzo[a,c]carbazole derivatives were synthesized in good yield through reaction of methyl 7-oxo-dehydroabietate with a variety of substituted phenylhydrazines. The structures of the newly synthesized compounds were confirmed by IR, 1H NMR, MS spectral studies and elemental analysis. All compounds were investigated for their activity against four bacteria (Bacillus subtilis, Staphylococcus aureus, Escherichia coli and Pseudomonas fluorescens) and three fungi (Trichophyton rubrum, Candida albicans and Aspergillus niger). Among the compound tested, 6d, 6e, 6f and 6m exhibited pronounced antibacterial activities and 6e and 6m also showed moderate antifungal activities. Particularly, 6d exhibited stronger antibacterial activity against B. subtilis comparable to positive control.
- Gu, Wen,Wang, Shifa
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experimental part
p. 4692 - 4696
(2010/10/03)
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- Synthesis and structure of indoline spiropyrans of the coumarin series
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New indoline spiropyrans of the coumarin series were synthesized by the condensation of indoline and hydroxyformylcoumarin derivatives. Spiropyrans, viz., derivatives of 8-formyl-7-hydroxy-4-methylcoumarin and 5-formyl-6-hydroxy-4-methylcoumarin, under irradiation are transformed into open forms, which are recyclized in the dark. The compounds formed by the condensation of the indoline derivatives with 3-formyl-4-hydroxycoumarin have an open structure of the merocyanine dyes and are transformed into spiro forms neither in the dark nor under irradiation with the visible light.
- Traven,Miroshnikov,Chibisova,Barachevsky,Venidiktova,Strokach
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p. 2417 - 2424
(2007/10/03)
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- An efficient and safe procedure for the large-scale Pd-catalyzed hydrazonation of aromatic chlorides using buchwald technology
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A convenient, optimized and safe synthesis of N-arylhydrazines, useful as intermediates for active ingredients in agricultural and pharmaceutical applications, is reported. Starting from aryl halides (chlorides and bromides), a palladium-catalyzed carbon-nitrogen coupling reaction followed by an acidic treatment afforded the target molecules in good to excellent yields using low catalyst loadings. This technology has then been successfully applied on a large scale in a pilot plant. This contribution also describes the major improvements in ligand synthesis and the thermal data required to develop a process on a pilot scale.
- Mauger, Christelle C.,Mignani, Gerard A.
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p. 1065 - 1071
(2013/09/03)
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- Syntheses of 4-(5-oxo-1,2,4-triazol-3-yl)-sydnones and 4(4-arylamino-5-oxo-1,2,4-triazol-3-yl)-sydnones from sydnone derivatives and their fragments
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4-(5-oxo-1,2,4-triazol-3-yl)-sydnones 11 and 4-(4-arylamino-5-oxo-1,2,4-triazol-3-yl)-sydnones 13 have been obtained from a-chloroformylarylhydrazine hydrochloride 2. Moreover, the intermediates, including 3, 4, 9 and 10, in this study are synthetically informative and valuable. It is also noteworthy that three reactants, 1, 2 and sydnonecarbaldehydes, were prepared from sydnone derivatives and their fragments. The oxidative cyclizations of sydnonecarbaldehyde semicarbazones 9 and carbazpnes 10 with two different oxidizing agents (Cu(ClO4)2 and Fe(ClO4)3) have been extensively examined. The reaction time and the yields of cyclizations were affected by the substituents of semicarbazones 9 and carbazones 10.
- Kuo,Lee,Yeh
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p. 227 - 240
(2007/10/03)
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- Syntheses of α-Haloformylarylhydrazines and Their Self-dimerizations
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α-Haloformylarylhydrazine hydrohalides 1 were prepared through ring opening of 3-aryl-4-halosydnones 7 with hydrohalic acids in EtOAc in moderate yields.Reactions between compounds 1 and primary alcohols gave alkyl 1-arylhydrazinecarboxylates 12 and 14, important intermediates in syntheses of antiinflammatory drugs.Compounds, 16, 4-aryl-2-(arylhydrazin-1-yl)-1,3,4-oxadiazolin-5-ones, and compounds 18, 1,4-diaryl-1,4-dihydro-1,2,4,5-tetrazine-3,6-(2H,5H)-diones, were synthesized by self-dimerization of compounds 1.Compounds 18 were also converted to compounds 17 via intramolecular rearrangement.Structural elucidation and verification of the reaction mechanisms are presented.Key Words 3-Aryl-4-halosydnone; α-Haloformylarylhydrazine hydrohalide; Acid hydrolysis; Self-dimerization; Intramolecular rearrangement.
- Kuo, C. N.,Wu, M. H.,Chen, S. P.,Li, T. P.,Huang, C. Y.,Yeh, M. Y.
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p. 849 - 856
(2007/10/03)
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