Amidines amidrazones

The preparation of sugar amidines, amidrazones and amidoximes as inhibitors of carbohydrate-processing enzymes has been reviewed. Treatment of 2-deoxy-o-arabino-hcxose oxime with chloramine-T gave 2-deoxy-D-arafeino-hexono-l,4-oximinolactone, but the intermediate nitrones formed from this and 2-deoxy-o-... 

Addition of iV-nucleophiles converts nitriles into amidoximes, amidines, amidrazones, etc., which are valuable intermediates, especially for the preparation of heterocycles. For example amidoxime prepared from p-hydroxybenzo[ C]nitrile and hydroxylamine, reacted with nicotinoyl chloride to give 3,5-disubstituted l,2,4-[3- C]oxadiazole the... 

More exotic thioureas were the products of interesting reactions of isothiocyanates with ketimines, enamines imino-esters/ amidines, amidrazones, and substituted ammonium salts. Some selenoureas have been synthesized by the reaction of isoselenocyanates with amines, and the phosphorus compounds (300) were obtained analogously by treatment of w-mercaptoalkylphenylphosphines with phenyl isothiocyanate. The action of primary amines on (300) resulted in the formation of N-alkyl-lsT-phenylthioureas in high yields with simultaneous regeneration of the w-mercaptoalkylphenylphosphine. ... 

Condensation of amine 277 with dimethylformamide dimethylacetal (DMF/DMA) gave A, A-dimethyl-./V -(5-methyl-l, 2,4-triazolo[l, 5-a]pyrim-idin-7-yl)formamidine (278), whose reaction with hydroxylamine gave the formamidoxime 279 (89EGP264438 90ZC320).The amine 280 and the hydrazine 282 can be transformed into the amidine 281 and amidrazone 283, respectively (90ZC320) (Scheme 54). 

Sulfonyl halides (e.g. benzenesulfonyl chloride) form adducts (11) with acid amides in an equilibrium reaction. From these adducts or via adducts of this type 0-sulfonated lactim ethers, isonitriles, adenine, nitriles, amidines, amidinium salts and formic acid esters were prepared. The adducts from DMF and chlorosulfonamides (12) can be used to prepare amidines or amidrazones. A/-Chlorosulfonylcarboxylic acid amides yield nitriles on treatment with DMF or other tertiary amides, presumably via an acid amide sulfonyl chloride complex (13 equation 3). ... 

Amidine and amine groups may be joined together to form this triazepinone ring by heating the compound with methanolic sulphuric add for 3h. The reactant is obtained by stirring isatoic anhydride (review of reactions [3008]) with an amidrazone (formally, a hydrazone of a carboxamide). 

Cycloaddition of 1,2,4,5-tetrazines with C-N double or triple bonds yields dihydro-1,2,4-tri-azines 13 or 1,2,4-triazines 14 (see Section B.2.2.1.3.). Various systems with C—N double bonds have been used imines, including dihydropyrroles and dihydroisoquinolines 341 344 hydra-zones, including dihydropyrazoles,343 348 oxime ethers,343 imidates, including dihydrooxa-zoles 345 357 thioiniidates, including dihydrothiazoles 345,349,350 357 358 amidrazones 357,358 amidines 359 and isocyanates or isothiocyanates.351 Nitriles are the examples of systems with a C-N triple bond.352 -356... 

Allgemeine Synthese trisubstituierter Amidine. Amidoxime und Amidrazone... 

Tetra-O-acetyl-P-D-galactopyranosyl cyanide and the unsaturated nitrile 67 could be deacetylated under mild conditions (dilute NaOMe in MeOH at 0°C). Under less gentle conditions, 67 was converted into the crystalline imidate 68, and thence into the amidine 69, amidrazone 70, imidazole 71 and the corresponding benzimidazole (Scheme 13). ... 

This reaction has been extended to the trimerization of imidates, and the reaction between amidine salt and imidate. In addition, the reaction between amidrazone and Q, -dicarbonyl compounds has been used for the preparation of a -triazines or 1,2,4-... 

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