[2+2+2]-Cocyclotrimerization of 6-Alkynyl-7-benzylpurines with alpha,omega-Diynes

Abstract

6-Alkynyl-7-benzylpurines were prepared by the Sonogashira reaction from 6-chloro-7-benzylpurines and terminal alkynes. The prepared alkynylpurines were cyclotrimerized with various 1,6-diynes in the presence of Ni(cod)2/2PPh3 catalytic system into the corresponding 6-aryl-7-benzylpurines under ambient conditions.

The prepared 6-alkynyl- and 6-aryl-7-benzylpurines were tested for cytostatic activity.

Keywords

• [2+2+2]-cocyclotrimerization
• 6-Alkynyl-7-benzylpurines
• alpha
• omega-Diynes