p-Toluenesulfonic acid → HCID 14053130, compound

Participants

Reaction Steps

To a solution of 0.14 g of 2-amino-5-[(4-acetyl-3-hydroxy-2-propylbenzyl)thio]-1,3,4-thiadiazole obtained in Example 5 and 0.15 g of mono-p-methoxybenzyl malonate in 3 ml of pyridine were added 0.15 g of dicyclohexylcarbodiimide and a catalytic amount of p-toluenesulfonic acid. The resultant mixture was stirred at room temperature for 6 hours. During the stirring, 0.15 g each of mono-p-methoxybenzyl malonate and dicyclohexylcarbodiimide were supplemented to the system. After completion of the reaction, ethyl acetate was added to the system. After insoluble matters were filtered off, the filtrate was concentrated under reduced pressure. The obtained residue was dissolved in chloroform. The solution was washed with, in sequence, 1N hydrochloric acid, water, a saturated aqueous sodium bicarbonate solution and water and then, dried over anhydrous magnesium sulfate. The solvent was then removed by distillation. The resultant residue was subjected to silica gel column chromatography followed by elution with a mixture of chloroform-methanol (4:1). The eluate was recrystallized from isopropyl alcohol to give 0.04 g of p-methoxybenzyl 3-[[ 5-[(4-acetyl-3-hydroxy-2-propylbenzyl)thio]-1,3,4-thiadiazol-2-yl]amino]-3-oxopropionate.

Provenance & Evidence