4-[(4,5-Dihydro-2-thiazolyl)amino]tetrahydro-3,5-bis[(4-methoxyphenyl)methylene]thiopyran-4-ol-1,1-dioxide → 2,3,8,9-Tetrahydro-5-(4-methoxyphenyl)-9-[(4-methoxyphenyl)methylene]-5H,6H-thiazolo[3,2-a]thiopyrano[4,3-d]pyrimidine-7,7-dioxide

Participants

Reaction Steps

A suspension of 4-[(4,5-dihydro-2-thiazolyl)amino]-tetrahydro-3,5-bis[(4-methoxyphenyl)methylene]thiopyran-4-ol-1,1-dioxide (6.0 g, 0.012 mole) in 75 ml of n-BuOH and 25 ml of DMSO is stirred and heated at reflux for 1 hour. The volume of the resulting solution is reduced by approximately one-half using a Dean-Stark trap. After cooling, the yield of yellow product is 4.7 g, m.p. 235°-240°. Crystallization from 25 ml of DMF gives 4.0 g (69%) of cream colored product, m.p. 243°-245°.

Provenance & Evidence