2-氨基-4-氯-5-醛基噻唑合成工艺

以氯乙酸和硫脲为原料合成了2-亚氨基噻唑-4-酮,再与Vilsmeier试剂作用,经缩合水解得到2-氨基4-氯-5-醛基噻唑,总收率达到86％。     

Reactions with 5-Substituted 2-Thiazolidinone-4-thiones. Part IV

5-Arylidene-2-thiazolidinone-4-thiones 1 undergo Michael type reactions with Ω-nitrostyrene, α,β-unsaturated ketones and N-arylmaleimides to give the corresponding 7-aryl-tetrahydro-7H-thiopyrano[2,3-d]thiazole-2-one derivatives 3 and 4 . Arylmagnesium bromides add to the lateral double bond of 5-arylidene-3-phenyl-2-thiazolidinone-4-thiones 5 to yield products 6 . With phenyl-hydrazine at room temperature, 1 or 5 yield the corresponding aldehyde phenylhydrazones and 4-phenyl-hydrazono-2-thiazolidinone or its 3-phenyl derivative. The thione group in 5-diaryl-methyl-2-thiazolidinone-4-thiones condenses with phenylhydrazine to yield 5-diarylmethyl-4-phenyl-hydrazono-2-thiazolidinones 9 .     

Reactions with 5-substituted 4-arylimino-2-thiazolidinones

The reaction of 5-arylidene-4-arylimino-2-thiazolidinones 4 with GRIGNARD reagents effected 1,4-addition to the exocyclic  CC bond with the formation of 5 . Alkylation of the arylidene derivatives 4 with diazomethane or methyl iodide results in the formation of the N-methyl derivatives 6 . Treatment of 6 with phenylmagnesium bromide effects addition of the reagent to the double bond of the lateral chain to yield products, proved to have structure 8 . The 5-arylazo derivatives 9 of 4-arylimino-2-thiazolidinones were obtained by coupling 4 with aromatic diazonium chlorides. Compounds 9 were N-methylated with diazomethane to yield 10 .     

Synthesen mit 1,3-Dithietanen. IX [1]. Reaktionen des 2,4-Bis-(äthoxycarbonyl-cyan-methylen)-1,3-dithietans und des 2-Cyan-3,3-bis-(methylmercapto)-acrylsäureäthylesters mit Carbonsäurehydraziden

Syntheses with 1,3-Dithietanes. IX. Reactions of 2,4-Bis(ethoxycarbonyl-cyano-methylene)-1, 3-dithietane and of Ethyl 2-cyano-3, 3-bis(methylmercapto)acrylate with Carboxylic Acid Hydrazides 2, 4-Bis(ethoxycarbonyl-cyano-methylene)-1, 3-dithietane 1 reacts with carboxylic acid hydrazides to yield ethyl 1-aroyl-5-imino-3-mercapto-Δ³-pyrazoline-4-carboxylates 4. 4 and hydrazin hydrate yield ethyl 1-aroyl-5-imino-3-hydrazino-Δ³-pyrazoline-4-carboxylates 5 which are transformed by heat to the ethyl 3(5)-amino-5(3)-(2-aroyl-hydrazino)pyrazole-4-carboxylates 6 . The reaction of ethyl 2-cyano-3,3-bis(methylmercapto)acrylate 8 with carboxylic acid hydrazides yield ethyl 1-aroyl-3-amino-5-methylmercapto-pyrazole-4-carboxylates 10 . Compounds 10 are compared with S-methyl derivatives of 4 .     

Reactions with 5-Substituted 2-Thiazolidinone-4-thiones (isorhodanines). III

Treatment of 5-arylidene-2-thiazolidinone-4-thiones 1 with diazomethane in etherchloroform mixture effects N-methylation beside S-methylation to give the products 2 and 3 respectively. The S-alkylated derivatives 2 and 4 are obtained exclusively by the treatment of 1 with ethereal diazomethane or with ethyl bromoacetate, respectively. The N-piperidinomethyl and N-morphilinomethyl derivatives 5 were obtained by the MANNICH reaction on 1 . The reaction of 1 with acrylonitrile or ethylacrylate in pyridine medium at room temperature yields the products 6 . Subjecting 5-arylazo-2-thiazolidinone-4-thiones 7 to the action of ethereal diazomethan gives both the S- and N-methylated derivatives 8 and 9 , respectively. Subjecting 5-arylazo-4-methylmercapto-3-thiazolin-2-ones 8 to the action of aniline yields 5-arylazo-4-phenylimino-2-thiazolidinones 10 .     

Regioselective oxidation and halogenation of 2-(arylsulfenylimino)- and 2-(arylsulfinylimino)-4-thiazolines

The synthesis of 4-thiazoline 2-iminium sulfinates ( 3 ) is described. From the salts 3 and NBS the 2-(arylsulfonylimino)-4-thiazolines ( 4 ) were formed, which have also been prepared by oxidation of 2-(arylsulfenylimino)-4-thiazolines ( 5 ) and by reaction of the arylsulfonyl chlorides ( 6 ) with 2-imino-4-thiazolines ( 2 ). The treatment of 5 with NBS (or NIS) in dry solvents results in 2-(arylsulfenylimino)-5-bromo (or iodo)-4-thiazolines ( 7 ); in the presence of NaHCO₃ 2-(arylsulfonylimino)-5-bromo-4-thiazolines ( 8 ) are formed. 2-(Arylsulfinylimino)-4-thiazolines ( 10 ) have also been halo- genated in the same manner with NBS or NIS to give the products ( 11 ).     

Zur Herstellung von 1,3,4- Oxadiazol-2-carbonsäurederivaten

Preparation of 1,3,4,-Oxadiazol-2-carboxylic Acid Derivatives The synthesis of 5-substituted-1,2,4-oxadiazol-2-carboxylic acid derivatives 3a-g and 4a-g by cyclodehydratation of diacylhydrazines 1a-g and 2a-g are described. Further derivatives 6 to 9 are obtained from 1,3,4-oxadiazol-2-carboxethyl esters 3 .     

异硒氰酸酯参与合成2-亚胺基-1,3-硒唑-4-酮类化合物的研究

以异硒氰酸酯、苄胺、氯乙酰氯为原料,在三乙胺的作用下一锅法反应合成2-亚胺基-1,3-硒唑-4-酮衍生物,收率良好。其结构经1H NMR,13C NMR,IR和MS表征。     

Cyansäureester, 27 [1]. Triazino-benzimidazole aus 2-Amino-benzimidazol-1-imidsäureestern und carbonylanalogen Verbindungen

Cyanic Acid Esters. 27. Triazino-benzimidazoles from 2-Amino-benzimidazole-1-imid-esters and Carbonyl Analogic Compounds The Cyclocondensation of 2-amino-benzimidazole-1-imid-esters with aldehydes, carbonic acid anhydrides and isocyanates has been investigated. With aldehydes in the presence of piperidine 4-aryloxy-1,2-dihydro-1,3,5-triazino[1,2-a]benzimidazoles 3 and with carbonic acid anhydrides 4-aryloxy-1,3,5-triazino[1,2-a]benzimidazoles 5 are formed. Isocyanates react with the imid esters to the corresponding 3-substituted ureas 8 which on heating undergo acyl migration of the carbamoyl group followed by cyclocondensation to 4-imino-2-oxo-1,2,3,4-tetrahydro-1,3,5-triazino[1,2-a]benzimidazoles 12 .     

2-取代-4-氯-5-芳基-2H-1,2,3-三唑类化合物的合成及其生物活性

为发现杀菌活性高、抑菌谱广的新化合物，以芳醛、硝基甲烷及叠氮化钠为起始原料，经环化、氯化、烃化反应合成了15个2-取代-4-氯-5-芳基-2H-1,2,3-三唑类新化合物，目标物的分子结构经核磁共振谱、质谱和元素分析进行了确证。采用菌丝生长速率测定法，在25 mg/L的测试浓度下，目标化合物对小麦赤霉病菌、辣椒疫霉病菌、烟草赤星病菌、黄瓜灰霉病菌、水稻纹枯病菌及油菜菌核病菌6种作物病菌进行了离体抑菌活性试验。初步的抑菌活性测试结果表明：化合物4d对小麦赤霉病菌、黄瓜灰霉病菌及油菜菌核病菌的抑制率分别为70.4%、74.1%和72.9%，化合物4k对黄瓜灰霉病菌及油菜菌核病菌的抑制率分别为87.0%及84.7%。4d对辣椒疫霉病菌的抑制率为61.4%，高于商品化品种苯醚甲环唑的42.5%。     

Reactivity of the exocyclic double bond in 4-arylidene-2-phenyl-2-imidazolin-5-ones toward organomagnesium compounds. I

4-Arylidene-2-phenyl-1-substituted-2-imidazolin-5-ones 1a – d react with organomagnesium compounds, in ether at room temperature, to yield, as the main isolable products, the 4-disubstituted-methyl derivatives 2a – h . On the other hand, 1a – d react with phenylmagnesium bromide in a boiling ether-benzene mixture to give, among the reaction products, 2a – d and the 4-diarylmethylene derivatives 3a – d . Spectral data of 2 and 3 are discussed. Treatment of the GRIGNARD products 2a – c with formaldehyde and piperidine or morpholine effects aminomethylation at C-4 with the formation of the MANNICH bases 6a – f .     

Synthesis of 2-imino-1,3-dithiolanes containing trimethylsilylethynylthiolato groups

An efficient, eco-friendly, and simple one-pot approach for the synthesis of 2-imino-1,3-dithiolanes via reaction of allyl chloride, primary amines, carbon disulfide, and I₂ under solvent-free conditions is presented. The obtained 5-iodomethyl-2-imino-1,3-dithiolanes were converted into silyl-protected terminal alkynyl sulfides substituted 2-imino-1,3-dithiolanes by treatment with lithium 2,2,2-tris(trimethylsilyl)ethanedithioate, produced by the reaction of tris(trimethylsilyl)methyllithium (TsiLi) with CS₂.     

Versatile 2-amino-4-substituted-1,3-thiazoles: synthesis and reactions

Syntheses and reactions of 2-amino-4-substituted-1,3-thiazoles are reviewed in a formal way. The title compounds are most easily accessible by various approaches, and even waste-free solid-state procedures have been developed. The substitution in 4-position has synthetic reasons and therefore most interest accumulates around these derivatives of 2-aminothiazole. The high reactivity of both the amino group and the positions 3 and 5 of the 1,3-thiazole ring are used for numerous syntheses in a comprehensive way. The reactions are subdivided in groups that cover reactions at the amino substituent without touching the thiazole ring, reactions which involve both nitrogens in the formal amidine system to give thiazolo-pyrimidinones and -imidazoles as well as more involved polycondensed N,S-heterocycles with multiple possibilities for substituents, and substitution reactions at the 5-position of the thiazole ring. Most of the imaginable reaction types have been successfully applied and used, as many of the synthesized compounds exhibit interesting biological activity in various fields.     

Regio- and stereoselectivity of 1-(Pyridazin-3-yl)-3-oxidopyridinium Betaines towards 2π- and 4π-conjugated olefins

1-(6-Phenyl) and 1-(6-(4-tolyl)-3-oxidopyridinium betaines ( 1a , b ) react as 1,3-dipoles with conjugated olefines, namely 4-vinylpyridine, ethyl cinnamate and styrene as 2π-1,3-dipolarophiles to give 2,6-cycloadducts [6-substituted-8-azabicyclo[3,2,1]oct-3-en-2-ones ( 3a , b , 4a , b and 5b )] and with butadiene and furan as 4π-dipolarophiles to give 2,4-cycloadducts [7-substituted-7-azabicyclo[4,3,1]deca-3,8-diene-10-one] and 3-6-phenylpyridazin-3-yl)-3-aza-10-oxatricyclo-[5,2,1,1^2,6]undeca-4,8-diene-11-one ( 9a ). Structural and configurational assignments were based on H.n.m.r. spectral analysis.     

Reactions of α-Arylhydrazono-β-oxo-β-phenyl-propionitriles

ω-Cyanoacetophenone was coupled with a variety of aromatic diazonium chlorides to give the corresponding arylazo derivatives 1 a – g . Analysis of the IR and UV spectra of these compounds indicated that they exist mainly as the corresponding arylhydrazones. Compounds 1 a – d, f, g reacted with diazomethane to yield the N-methyl-arylhydrazones 2 a – f . 3-Amino-4-arylazo-5-phenylpyrazoles 5 a – g and 4-arylazo-5-imino-1,3-diphenyl-2-pyrazolines 6 a – g were obtained by the interaction of 1 a – g with hydrazine hydrate and with phenylhydrazine, respectively.     

2-取代-4(3H)-喹唑啉酮类化合物合成研究进展

综述了2-取代-4(3H)-喹唑啉酮类化合物几种主要的合成方法,主要介绍了包括以2-氨基苯甲酸、2-氨基苯甲酰胺、2-氨基苯甲腈、2-氨基苯甲酸酯等为原料的合成方法,并对这些方法进行了简单的评述。     

A convenient synthesis of alkyl-2-(2-imino-4-oxothiazolidin-5-ylidene)acetate derivatives involving an electrogenerated base of acetonitrile

We report a simple method for the synthesis of alkyl-2-(2-imino-4-oxothiazolidin-5-ylidene) acetate derivatives 3 in good yields under mild conditions. The electrogenerated cyanomethyl base (EGB), obtained from electroreduction of acetonitrile-0.1?M TBABF₄, assists the reaction between thiourea derivatives 1 and dialkyl acetylene dicarboxylate 2. The expected products, 3/4, and the structure obtained from X-ray diffraction confirm that the main products are the five-membered heterocycles 3. Furthermore, a mechanism, to explain the reaction pathways, is proposed based on the thermodynamic and kinetic data obtained from quantum calculations.     

Stability Constants of Oximes of 4-Substituted-2-acetylphenols [1]

Proton-ligand stability constants (pKd) and metal-ligand stability constants for six oximes of 4-substituted-2-acetyl phenol in H₂O: Dioxane (1:3) are obtained by the spectrophotometric method of Magnusson et al. as modified by Patel et al.     

Synthesis,Spectroscopy and Tautomeric Study of Thiazoles substituted in positions 2 and 4 by hydroxy,mercapto and amino groups

Thiazoles substituted in positions 2 and 4 by hydroxy, mercapto and amino groups were synthesized, as well as its carbamate derivates and formylhydrazones. The research of the reaction of the formylhydrazide with 4-imino-2-thiazolidinone has not given the pyrazolo [3,4-d]- thiazol-2-one, but the 4-formylhydrazono-2-thiazolidine. The detailed tautomeric study of each of the heterocyclic compounds has been carried out by infrared spectroscopy, nuclear magnetic resonance of proton and of 13-carbon, and of masses.     

Synthesis of Thiazolo(4,5-b)-quinoxalines and related compounds

The reaction of 2,3,7-trichloroquinoxaline ( 1 ) or 2,3-dichloro-7-bromoquinoxaline ( 2 ) with thiourea in DMSO gave 6,6′-dichloro- or 6,6′-dibromodiquinoxalino[2,3-b:2′:3′-e]1,4-dithiien ( 3 or 4 ). However, 1 or 2 reacts with thiourea in ethanol to give ( 3 or 4 ) beside 7-chloro- or 7-bromo-2-imino-2,3-dihydrothiazolo[4,5-b] quinoxaline ( 5 or 6 ) respectively. Interaction of 1 or 2 with acetone thiosemicarbazone gave 7-chloro- or 7-bromo-3-amino-2-imino-2,3-dihydro-thiazolo[4,5-b] quinoxaline hydrochloride ( 13 or 14 ) respectively. Cyclization of 7-chloro- or 7-bromo-3-amino-2-imino-2,3-dihydrothiazolo[4,5-b]quinoxaline ( 15 or 16 ) on treatment with aromatic acid chlorides or isothiocyanates succeeded to give 19—21 or 28 and 29 .