Microwave-assisted ring closure reactions: synthesis of 8-substituted xanthine derivatives and related pyrimido- and diazepinopurinediones.

ABSTRACT:

Background

Poly-substituted xanthine derivatives are an important class of compounds in medicinal chemistry. Substitution at the 8-position of the purine ring is generally accessible by ring closure of a carboxamido-substituted uracil precursor. Although several procedures to accomplish this synthetic step have been suggested, it still remains difficult in many cases.

Results

Ring closure reaction with hexamethyldisilazane was studied under microwave conditions. Reaction times were dramatically reduced by the application of microwaves in the syntheses of the 8-styrylxanthine derivative istradefylline, and in the preparation of 2-substituted pyrimido [1,2,3-cd]purines. Furthermore, the new procedure allowed the preparation of a previously unaccessible diazepino [1,2,3-cd]puri

SUBMITTER: Burbiel JC 

PROVIDER: S-EPMC1698928 | biostudies-literature | 2006 Oct

REPOSITORIES: biostudies-literature