6,7-Methylenedioxy-1-(3',4'-methylenedioxyphenyl)naphthalene-2, 3-dicarboxylic acid anhydride AIDS-156648 AIDS156648 Ethyl acetate compound with 5-(1,3-benzodioxol-5-yl)furo[3',4':6,7]naphtho[2,3-d][1,3]dioxole-6,8-dione (1:1) NSC627696