反应详情

Convert 2.22 g of 7-benzyloxycarbonyl-1,4-dithia-7-azaspiro[4.4]nonane-8(S)-carboxylic acid, ethyl ester (prepared as described in paragraph A) to 1,4-dithia-7-azaspiro[4.4]nonane-8(S)-carboxylic acid, ethyl ester as described in Example 1 and couple this compound with 1.5 g of N-benzyloxycarbonylglycine, N-hydroxysuccinimide ester as described in Example 2 to yield 7-(N-benzyloxycarbonylglycyl)-1,4-dithia-7-azaspiro[4.4]nonane-8(S)-carboxylic acid, ethyl ester, a yellow oil [α]D24 -15.9°. (ethanol).