Antineoplastic Diterpene−Benzoate Macrolides from the Fijian Red Alga <i>Callophycus serratus</i>

Three diterpene−benzoate natural products, with novel carbon skeletons and an unusual proposed biosynthesis, were isolated from extracts of the Fijian red alga Callophycus serratus and identified by a combination of X-ray crystallographic, NMR, and mass spectral analyses. Bromophycolide A (1) displayed cytotoxicity against several human tumor cell lines via specific apoptotic cell death. This represents the first discovery of natural products incorporating a diterpene and benzoate skeleton into a macrolide system.三种二萜-苯甲酸酯天然产物（diterpene−benzoate natural products）具有新颖的碳骨架，其推测的生物合成途径非同寻常。该类产物从采自斐济的红藻Callophycus serratus的提取物中分离得到，并通过X射线晶体衍射、核磁共振（NMR）与质谱分析联用的手段完成鉴定。溴藻内酯A（Bromophycolide A，1）可通过诱导特异性细胞凋亡，对多种人肿瘤细胞系展现出细胞毒性。此项研究首次发现了将二萜与苯甲酸酯骨架整合到大内酯（macrolide）环系中的天然产物。