Chemical Studies on Super Carbon Cbain Compounds Produced by Dinoflagellates.

海洋生物产生具有显著生物活性的新型化合物。我们的研究是为了弄清冈田酸和棒曲霉毒素等超碳链化合物的真正来源。培养出了两种典型的超碳链化合物。对这些分子的结构进行了解析。然而，由于这里分离的毒素是复杂的和相对较大的分子，最终的结构信息尚未获得。从分布于日本多岩石的太平洋海岸的典型海绵Halichondria okadai Kadota中分离出一系列Halichondrins。例如，灯盏花素B具有显著的抗肿瘤活性，是抗癌药物的候选药物。虽然延胡索乙素已被岸信群完全消化，但我们仍需提供克量级的药物用于临床试验。由于不可能从黑色海绵中获得这些物质，我们已经开始寻找真正的天然灯盏花素生产者，因为怀疑是细菌或蓝藻等海洋微生物。从宿主动物中分离出细菌，并在海洋琼脂中进行培养。通过监测这些培养液的抗真菌活性，我们分离出了伊图林和普伐他汀等脂肽。

Marine organisms produce novel compounds with remarkable biological activitites. Our studies have been carried out in order to clarify the true producers of the super carbon chain compounds such as okadaic acid and palytoxin.The symbiotic dinoflagellate isolated Acoela sp. was cultured to give us two typical super carbon chain compounds. The structure elucidation of these molecules has been carried out. However, the final sturctural information has not yet obtained because the toxins isolated here are to be complex and relatively large molecule. From the typical marine sponge, Halichondria okadai Kadota distributed on the rocky Pacific shores of Japan, we isolated a series of halichondrins. For example, halichondrin B exhibits remarkable antitumor activity and is a candidate of anticancer drugs. Although halichondrin B has been totally sunthesized by Kishi's group,we have to supply the amount of gram-scale toward clinical test. Since it is impossible to obtain those from the black sponge, our search for the true natural producers of halichondrins has started because marine microorganisms such as bacteria or blue-green algae are suspected. Bacteria were isolated from the host animal and cultured in marine agar medium. Monitoring antifungal activities of these cultured medium led us to the isolation of lipopeptides such as iturin and plipastatin.