steroid fundamental parent cholane 0 330.329 330.59028 C24H42 CHEBI:35519 InChI=1S/C24H42/c1-5-8-17(2)20-12-13-21-19-11-10-18-9-6-7-15-23(18,3)22(19)14-16-24(20,21)4/h17-22H,5-16H2,1-4H3/t17-,18?,19+,20-,21+,22+,23+,24-/m1/s1 QSHQKIURKJITMZ-BRPMRXRMSA-N [H][C@@]1(CC[C@@]2([H])[C@]3([H])CCC4CCCC[C@]4(C)[C@@]3([H])CC[C@]12C)[C@H](C)CCC chebi_ontology cholane