Novel process and intermediates for production of cabergoline and related compounds

Abstract

A process for preparation of N-(ergoline-8β-carbonyl)ureas of the formula [I] their stereoisomers as well as acid addition salts thereof which process comprises silylating an ergoline-8β-carboxamide of the formula [2], 1 their stereoisomers as well as metal or ammonium salts or acid addition salts thereof and reacting the resultant product with an isocyanates R1N═C═O [5] wherein R1 is selected from alkyl having from 1 to 4 carbon atoms, cyclohexyl, phenyl, and dimethylamino alkyl group —(CH2)nNMe2 in which n is an integer, R2 is selected from hydrogen, alkyl having from 1 to 4 carbon atoms, cyclohexyl, phenyl, dimethylamino alkyl group —(CH2)nNMe2 in which n is an integer, pyridyl, pyrimidyl pyrazinyl, pyridazinyl, thiazolyl or thiadiazolyl, R3 represent a hydrocarbon group having from 1 to 4 carbon atoms, and R4 is selected from hydrogen, halogen, methylthio and phenylthio group;; followed by desilylation. This novel approach provides an efficient method for preparation of N-(ergoline- 8β-carbonyl)ureas of the formula [I] which can be useful as anty-Parkisons drugs and prolactin inhibitors. One of the most potent antiprolactinic agent of the class of compounds prepared according to the present invention is Cabergoline Silylated ergolines, which are obtained as intermediates in the process of the present invention, are novel compounds and represent a further aspect of the invention.

Dependencies are inferred from the claim text.