Synthesis and biological activity of abscisic acid analogs.

脱落酸类似物的合成和生物活性。

• 批准号: 03660136
• 负责人: HIRAI Nobuhiro
• 金额: $ 1.41万
• 依托单位: KYOTO UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1991
• 资助国家: 日本
• 起止时间: 1991 至 1992
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-03660136/
• 关键词: Abscisic acid; Phaseic acid; Metabolism; Fluorination; Methoxyabscisic acid; Fluoroabscisic acid; 8'ーヒドロキシアブシジン酸; 8'ーメトキシアブシジン酸; 植物生長阻害物質

Abscisic acid (ABA) is deactivated by hydroxylation at C-8' followed by cyclization to phaseic acid in plants. Introduction of methoxy or fluorine to C-8' and 9' was planned to increase the activity through prevention against the deactivation.(*)-8'- and 9'-Methoxy derivatives were synthesized from hydroxymethyldimethylcyclohexanone, and optically resolved by HPLC with a Chiralpak AD column. (+)-8'-MethoxyABA was three times as active as (+)-ABA in a rice seedling test. The activity of (+)-9'-methoxyABA was ten times and twice higher than that of (+)-ABA in lettuce seeds and alpha-amylase induction tests, respectively. These methoxy derivatives are first analogs with higher activity than ABA. The high activity of 9'-methoxyABA suggests that the methoxy group at C-9' affects the affinity to receptor rather than metabolism. The activity of (-) forms were 1/10-1/400 of (+) forms. The difference of activity between (+) and (-) forms was larger than that in the case of ABA, supporting that methoxyABA might have higher affinity to receptor than ABA.Fluorination of hydroxymethyldimethylcyclohexanone and its aldehyde was tried with DAST. Monofluorination of the alcohol was difficult, but achieved in a yield of 30% from the cis dimethyl form. Difluorinated precursor was obtained in a yield of 40% from the aldehyde. Synthesis of monofluoro and difluoro-ABA is under progress. Biological activity of these derivatives will be tested.

脱落酸 (ABA) 在植物中通过 C-8' 羟基化而失活，然后环化为菜豆酸。计划在 C-8' 和 9' 上引入甲氧基或氟，通过防止失活来提高活性。(*)-8'-和 9'-甲氧基衍生物是由羟甲基二甲基环己酮合成的，并通过 HPLC 进行光学解析Chiralpak AD 柱。在水稻幼苗试验中，(+)-8'-MethoxyABA 的活性是 (+)-ABA 的三倍。在生菜种子和α-淀粉酶诱导试验中，(+)-9'-甲氧基ABA的活性分别比(+)-ABA高10倍和2倍。这些甲氧基衍生物是第一个具有比ABA更高活性的类似物。 9'-甲氧基ABA的高活性表明C-9'处的甲氧基影响与受体的亲和力而不是代谢。 (-)型的活性是(+)型的1/10-1/400。 (+)和(-)形式的活性差异大于ABA的活性差异，支持甲氧基ABA可能比ABA具有更高的受体亲和力。用DAST尝试了羟甲基二甲基环己酮及其醛的氟化。醇的单氟化很困难，但以顺式二甲基形式实现了 30% 的产率。由醛得到二氟化前体，收率为40％。单氟和二氟-ABA的合成正在进行中。将测试这些衍生物的生物活性。