Study of natural inducer for coral larval settlement and metamorphosis.

从甲壳珊瑚藻Hydrolithon reinboldii中分离到一种新的促进变态的巨噬细胞，即发光藻。通过光谱分析确定了其结构。一小部分经ODS凝胶柱层析，用80%甲醇水溶液洗脱，1.30 μg/mL的CCA提取物诱导幼虫变态（25.9±7.4%），添加1.0mg/L的1.0mg/L此外，制备了包括11-deoxyfistularine-3在内的8种溴酪氨酸衍生物，并测试了它们对石珊瑚Pseudosiderastrea tayamai幼虫的变态诱导活性。注意到以下结构-活性关系：（i）两个螺异恶唑啉部分是必需的，两个螺异恶唑啉部分之间的酪胺衍生物对于活性不是必需的。(ii)每个螺异恶唑啉部分中的两个羟基对于活性是重要的。

A new metamorphosis-enhancing macrodiolide, luminaolide, was isolated from the crustose coralline algae (CCA) Hydrolithon reinboldii. Its structure was determined by spectroscopic analysis. A fraction (1.30 μg/mL) eluted with 80% aqueous MeOH by ODS gel column chromatography of the same CCA extract induced larval metamorphosis (25.9±7.4%) against Leptastrea purpurea, and its metamorphosis-inducing activity was further enhanced to 92.6±2.9% with the addition of 1 (25.6 ng/mL).Furthermore, eight bromotyrosine derivatives including 11-deoxyfistularine-3 were prepared and tested for their metamorphosis-inducing activity against larvae of scleractinian coral Pseudosiderastrea tayamai. The following structure-activity relationships were noted : (i) two spiroisoxazolin moieties are essential, tyramine derivetive between both spiroisoxazolin moieties is not essential for the activity. (ii) Two hydroxyl groups in each spiroisoxazolin moiety are important for the activity.