Patent ID: 6846933

Claim:
A method for producing an antimycobacterial compound of the formula: wherein R 1 is H; and wherein R 2 is phenyl, substituted phenyl, napthyl or substituted napthyl or wherein R 1 when taken together with R 2 form optionally substituted carbocyclic groups; which comprises: refluxing with absolute ethanol to produce a solution; adding a carbonyl compound comprising the formula of: R 3 COR 4 (2) wherein R 3 ═H; and wherein R 4 =phenyl, substituted phenyl, napthyl and substituted napthyl; or wherein R 3 when taken together with R 4 form optionally substituted carbocyclic groups; to the solution to produce a reaction mixture, the reaction mixture having a mole ratio of carbonyl compound to compound (1) of 1.67 to 1.00; distilling the reaction mixture; precipitating a solid from the reaction mixture; filtering the solid; and drying the solid to obtain I.