analytical standard Synonym(s): (3 E ,4 S )-3-[2-[(1 R ,4a S ,5 R ,6 R ,8a S )-Decahydro-6-hydroxy-5-(hydroxymethyl)-5,8a-dimethyl-2-methylene-1-naphthalenyl]ethylidene]dihydro-4-hydroxy-2(3 H )-furanone; ent -(3β,12 E ,14 R )-3,14,19-Trihydroxy-8(17),12-labdadien-16,15-olide; Andrographis...