Synonyms: Formosanan-16-carboxylicacid, 11-methoxy-19-methyl-2-oxo-, methyl ester, (7a,19a)-; Spiro[3H-indole-3,6'(4'aH)-[1H]pyrano[3,4-f]indolizine]-4'-carboxylicacid, 1,2,5',5'a,7',8',10',10'a-octahydro-6-methoxy-1'-methyl-2-oxo-, methylester, [1'S-(1'a,4'aa,5'aa,6'a,10'ab)]-; Tetraphylline oxindole A