Reactions of Substituted Xanthotoxin with Nitriles and Hydrazines

Abstract

4-Bromoxanthotoxin reacts with cyanoacetamide to form 4-bromo-o,6-dihydroxantho- toxin, which on hydrolysis with cold hydrochloric acid leads to the formation of cyano- acetic acid derivative, but hydrolysis by boiled hydrochloric acid gives the acetic acid derivative. Thio-, and 4-nitroxanthotoxin reacts with malononitrile in presence of piperidine by addition to give thio- and 4-nitro-5,6-dihydroxanthotoxin-5-[1',3,,3'-tricyano-2-amino- propene-(2)] respectively, while in presence of ammonia leads to the formation of 5- malononitrile derivatives. The reaction of hydrazine and phenyl hydrazine with thio- and 4-bromothioxanthotoxin leads to the formation of the hydrazones. Also thio- and 4-bromothioxanthotoxin reacts with anhydrous aluminium chloride in benzene by cleavage of the furan ring and the formation of 6-(1,2-diphenylethyl)-7,8- dihydroxythiocoumarin and 5-bromo-6-(1,2-diphenylethyl)-7,8-dihydroxythiocoumarin, respectively