4-Chlorobenzylamine → [1,2,3]Thiadiazolo[5,4-d]pyrimidine

5-Hydroxy-5H-[1,3,4]thiadiazolo[3,2-a]pyrimidine-6-carboxamides. As described in Chart BL, (4-morpholinyl)acetic acid trifluoroacetic acid salt BL.1 (J. Med. Chem. 1994, 37, 4538-4554) is cyclized to the thiadiazole BL.2 with aminoguanidine in polyphosphoric acid. Condensation of BL.2 with diethyl ethoxymethylenemalonate followed by thermal cyclization affords thiadiazolopyrimidine BL.3. The resulting ester BL.3 is then saponified to afford the corresponding acid BL.4 which is then coupled with a benzylamine (e.g. 4-chlorobenzylamine) mediated by 1,1′-carbonyldiimidazole (or other suitable carboxylic acid activating agent) to provide amides of the general formula BL.5. A specific example of heterocycle W19.2 in which R8=OH is also prepared as described in Chart BL. Thiadiazole BL.2 is heated in xylenes with diethyl 2-(((4-chlorobenzyl)amino) carbonyl)malonate (prepared by the reaction of 4-chlorobenzyl-amine with triethyl methanetricarboxylate) to afford thiadiazolopyrimidine BL.6.

ORDレコード

ord-64ba85c69f244b278405064401e40157

出典データセット

uspto-grants-2003_05

DOI

10.6084/m9.figshare.5104873.v1

特許番号

US06559145B2