title: Racemosins A and B, two novel bisindole alkaloids from the green alga Caulerpa racemosa.
abstract: Racemosin A (1), a structurally unique bisindole alkaloid possessing the seco-indolo[3,2-a]carbazole skeleton with two uncommon indolinenone units both conjugated with a methyl propenoate moiety, and its unusual cyclized derivative, racemosin B (2), were isolated from the green alga Caulerpa racemosa, together with the most commonly encountered pigment in the genus Caulerpa, caulerpin (3). Their structures were elucidated by extensive spectroscopic analysis and by comparison with data for related known compounds. A plausible biosynthetic pathway of 1 and 2 was proposed. In a neuro-protective assay, compound 1 significantly attenuated the Aβ2(5-35)-induced SH-SY5Y cell damage with a 14.6% increase in cell viability at the concentration of 10μM when compared to epigallocatechin gallate (EGCG, 16.57% increase at 10 μM) as the positive control.
authors: School of Pharmacy, Nanchang University, 461 Bayi Road, Nanchang 330006, PR China.
authors: Ding-Quan
authors: DQ
authors: Liu
authors: School of Pharmacy, Nanchang University, 461 Bayi Road, Nanchang 330006, PR China; Institute of Translational Medicine, Nanchang University, Nanchang 330031, PR China. Electronic address: maoshuichun@ncu.edu.cn.
authors: Shui-Chun
authors: SC
authors: Mao
authors: State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, PR China.
authors: Hai-Yan
authors: HY
authors: Zhang
authors: School of Pharmacy, Nanchang University, 461 Bayi Road, Nanchang 330006, PR China.
authors: Xiao-Qing
authors: XQ
authors: Yu
authors: School of Pharmacy, Nanchang University, 461 Bayi Road, Nanchang 330006, PR China.
authors: Mei-Tang
authors: MT
authors: Feng
authors: School of Pharmacy, Nanchang University, 461 Bayi Road, Nanchang 330006, PR China.
authors: Bin
authors: B
authors: Wang
authors: School of Pharmacy, Nanchang University, 461 Bayi Road, Nanchang 330006, PR China.
authors: Li-Hua
authors: LH
authors: Feng
authors: State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, PR China. Electronic address: ywguo@mail.shcnc.ac.cn.
authors: Yue-Wei
authors: YW
authors: Guo
mesh_terms: D046068:Caulerpa / Q000737:chemistry*; D002470:Cell Survival / Q000187:drug effects; D006801:Humans; D026121:Indole Alkaloids / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D007211:Indoles / Q000737:chemistry / Q000302:isolation & purification; D015394:Molecular Structure; D009447:Neuroblastoma; D018696:Neuroprotective Agents / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D010936:Plant Extracts / Q000737:chemistry* / Q000494:pharmacology
chemical_list: D026121:Indole Alkaloids; D007211:Indoles; D018696:Neuroprotective Agents; D010936:Plant Extracts; C000588642:racemosin A; C000392:caulerpin
keywords: Bisindole alkaloids; Caulerpa racemosa; Green alga; Neuro-protective activity; Racemosins A and B