A convenient method has been developed for direct conversion of nitriles to amidines in high yields. The method can also be applied to the preparation of guanidines from N-alkyl cyanamides.
LY503430, an optically active β-fluoroamine, is a potential therapeutic agent for the Parkinson's disease. Different strategies have been studied to synthesize this molecule using a regioselective and stereospecific rearrangement of β-aminoalcohols into β-fluoroamines induced by DAST. This reaction allowed the synthesis of LY503430 with an excellent enantiomeric excess.
作者:Angela De Munno、Vincenzo Bertini、Nevio Picci、Francesca Iemma、Marco Pocci
DOI:10.3987/com-98-8144
日期:——
The key reagent 3,5-dichloro-4-pyridinecarbonitrile (1) was used to synthesize 4-aminomethylpyridine derivatives 3,5-disubstituted with various amino groups, very active as inhibitors of diamine oxidase. The study of the reaction allowed to discover conditions for the gradual substitution in good yields of the two chlorine atoms to give symmetrically and unsymmetrically disubstituted derivatives (3), or the substitution of the cyano group, or the formation of amidines. The reduction of the cyano to aminomethyl group in compounds (3) afforded the target bioactive products.
Towards the Synthesis of Calyculin: A Synthetic Intermediate Corresponding to the C(26)-C(37) Fragment
作者:Henry A. Vaccaro、Daniel E. Levy、Akiyoshi Sawabe、Thomas Jaetsch、Satoru Masamune
DOI:10.1016/0040-4039(92)88107-g
日期:1992.4
The synthetic intermediate 2 corresponding to the C(26)-C(37) fragment of calyculin A (1) has been synthesized. Key transformations include the efficient one-pot construction of the oxazole system embedded in 1 without epimerization-alpha [C(30)] to the ring, and the in situ formation of the dimethylamine by opening an N-methyllactam with Meerwein's reagent and trapping the resultant methylamine with formaldehyde.