Geodisterol, a novel polyoxygenated sterol with an aromatic A ring from the tropical marine sponge Geodia sp.

Origin of an ancient hormone/receptor couple revealed by resurrection of an ancestral estrogen

“…4A). Steroids with an aromatic A-ring and a lateral side chain have been identified in a tropical sponge ( 11 ), and the very molecule we propose as a proxy for this ancestral chordate steroid, 19-norcholesta-1,3,5(10)-trien-3-ol, was recently isolated from a soft coral ( 12 ). The synthesis of these molecules by nonbilaterian animals is probably related to defensive functions rather than to endocrine signaling ( 27 ).…”

“…For the sake of simplicity, we tested the ligand-binding ability of an aromatized steroid with a side chain and with no hydroxylation. We define “paraestrols” as steroids comprising a cholesterol side chain and an aromatized A-ring to avoid confusion with other natural products bearing additional modifications on the side chain, such as ethyl or methyl groups on carbon 24 ( 11 , 12 ). We further refer to 19-norcholesta-1,3,5(10)-trien-3-ol as paraestrol A, being the first member of this class to be synthesized de novo and experimentally characterized.…”

Reversal of Fluconazole Resistance by Sulfated Sterols from the Marine Sponge Topsentia sp.

“…14 [α] D +67 ( c 0.31, CH 2 C1 2 −MeOH 9:1)]; IR (NaCl) ν max 3379 (br), 2919, 1620, 926, 820 cm −1 ; NMR data (see Supporting Information) is in agreement with the literature values. 12 …”

“…and possessed an aromatic A ring. 12 On comparison of the NMR data of 1 with those of 3 , the close resemblance indicated that 1 was an O -sulfited derivative of 3 .…”

“…12 We have further examined the issue concerning the C-20 configuration in 1 . According to the results reported by Nes and Varkey, 14,15 free rotation around the C-17 − C-20 bond in 20-hydroxysteroids is hindered when C-20 is tetrahedral but is unhindered when C-20 is trigonal planar.…”