1-[(2-Acetoxyethoxy)methyl]-3-benzyl-6-phenyl-thieno[3,2-c][1,2,6]thiadiazin-4-one 2,2-dioxide AIDS-104970 AIDS104970 Acetic acid 2-(3-benzyl-2,2,4-trioxo-6-phenyl-3,4-dihydro-2H-2.lambda.6-thieno[3,2-c][1,2,6]thiadiazin-1-ylmethoxy)-ethyl ester