Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

Acetylated amino thiazoles,

Aromatic thioamides react with MeC(0)CHClC(0)C02Et to give a 3 1 ratio of ethyl 5-acetyl-2-aryl-thiazole-4-carboxylates and the isomeric products (2). Modifications of the Hantzsch synthesis continue to appear. Thus, 2-aryl-5-aroyl-thiazoles may be prepared from the JV -thioaroyl-iViV-dimethyl-formamidines ArC(S)N=CHNMea and a-bromo-ketones [strictly speaking, this is a Type F (C—N—C—S + C) synthesis], whilst 5-amino-2-phenyl-l,2,3-thiadiazolium salts [e.g. (3)] and compounds with the general structure RCHgCN (e.g. R = CN or COaEt) yield 4-amino-thiazoles. ... [Pg.357]

Chapter V. Quinaldine (V,2) 2-methyl-, 2 5-dimethyl- and 2-acetyl-thiophene (V,8-V,10) 2 5-dimethyl and 2 4-dimethyl-dicarbethoxy-p3nrole (V,12-V,13) 2-amino- and 2 4 dimethyl-thiazole (V,15-V,16) 3 5-dimethyl-pyrazole (V,17) 4-ethylp3rridine (from pyridine) (V,19) n-amyl-pyridines from picolines) (V,28) picolinic, nicotinic and isonicotinic acid (V,21-V,22) (ethyl nicotinate and p-cyanop3n idine (V,23-V,24) uramil (V,25) 4-methyl-(coumarin (V,28) 2-hyi-oxylepidine (V,29). [Pg.1191]

The general pattern of alkylation of 2-acylaininothiazoles parallels that of 2-aminothia2ole itself (see Section III.l). In neutral medium attack occurs on the ring nitrogen, and in alkaline medium a mixture of N-ring and N-amino alkylation takes place (40, 43, 161. 163). In acidic medium unusual behavior has been reported (477) 2-acetamido-4-substituted thiazoles react with acetic anhydride in the presence of sulfuric acid to yield 2-acetylimino-3-acetyl-4-phenyl-4-thiazolines (255) when R = Ph. but when R4 = Me or H no acetylation occurs (Scheme 151). The explanation rests perhaps in an acid-catalyzed heterocyclization with an acetylation on the open-chain compound (253), this compound being stabilized... [Pg.91]

The A-acetyl derivatives of the 2-alkylthio-l,3-thiadiazol-4-imines (124, R = SR, R = Ac) undergo nucleophilic displacement reaction with amines (benzylamine, cyclohexylamine, morpholine, or aniline) giving the 2-amino derivatives (124, R = NRj, R = Ac). The salt (126, R = R = Ph, R = R = H, X = Cl) reacts with aniline at room temperature giving 4-anilino-2-phenyl-l,3-thiazole (128), presumably by a mechanism involving cleavage of the heterocyclic ring. ... [Pg.29]

Thiamine pyrophosphate has two important coenzyme roles, both of which focus mostly on carbohydrate metabolism (Figs. 8.26 and 8.27). The active portion of the coen- rae is the thiazole ring. The first step in the oxidative decarboxylation of a-keto acids requires TPP. The two most common examples are pyruvate and a-ketoglutarate, oxidatively decarboxyatedto acetyl CoA and succinyl CoA, respectively. The same reaction is found in the metabolism of the branched-chain amino acids valine, isoleucine, leucine, and methionine. In all cases, TPP is a coenzyme in a mitochondrial multienzyme complex, consisting of TPP, lipoic acid, coenzyme A, FAD, and NAD. Note the number of vitamins required for the oxidative decarboxylation of a-keto acids thiamine (TPP), pantothenic acid (coenzyme A), riboflavin (FAD),and niacin (NAD). [Pg.389]

Durch Reaktion von Bis-[thioureido]-arenenmit l,4-Dibrom-2,3-dioxo-butanoder Bis-[brom-acetyl]-arenen ist es moglich, polymere 2-Amino-l,3-thiazole zu gewinnen270. [Pg.71]

Synthesis. - Type A Syntheses (S-C H -N + C). The C-nucleoside (182) is formed by condensation of 2-amino-4-chlorobenzenethiol with an acetylated aldonic nitrile or glycosyl cyanide followed by deacetylation23. 2-Aminobenzenethiol reacts with RC0CsCPh(Rs2-thienyl) to give (183). The latter cyclises to 2-phenylbenzo-thiazole on attempted recrystallisation (MeOH). With terminal acetylenic ketones a mixture of benzothlazolines results232. [Pg.177]


See other pages where Acetylated amino thiazoles, is mentioned: [Pg.289]    [Pg.588]    [Pg.78]    [Pg.120]    [Pg.122]    [Pg.209]    [Pg.228]    [Pg.203]    [Pg.122]    [Pg.236]    [Pg.139]    [Pg.21]    [Pg.46]    [Pg.67]    [Pg.279]    [Pg.327]    [Pg.40]    [Pg.122]    [Pg.279]    [Pg.280]    [Pg.492]    [Pg.646]    [Pg.439]    [Pg.21]    [Pg.130]    [Pg.228]    [Pg.383]    [Pg.32]    [Pg.60]    [Pg.91]    [Pg.235]    [Pg.1128]    [Pg.1185]    [Pg.1228]    [Pg.279]    [Pg.327]   


SEARCH



2-Acetyl Thiazole

2-Amino-4 thiazole

2-Amino-4- thiazoles

3-Acetyl-5-amino

© 2024 chempedia.info