p. 5225 - 5228
(2004)(3-carboxymethyl-1,4-dioxo-2a,10b-diphenyl-2a,3,4,5,10,10b-hexahydro-2,3,4a,10a-tetraaza-benzo[g]cyclopenta[cd]azulen-2-yl)-acetic acid
(3-chlorocarbonylmethyl-1,4-dioxo-2a,10b-diphenyl-2a,3,4,5,10,10b-hexahydro-2,3,4a,10a-tetraaza-benzo[g]cyclopenta[cd]azulen-2-yl)-acetyl chloride
(3-methoxycarbonylmethyl-1,4-dioxo-2a,10b-diphenyl-2a,3,4,5,10,10b-hexahydro-2,3,4a,10a-tetraaza-benzo[g]cyclopenta[cd]azulen-2-yl)-acetic acid methyl ester