SYNTHESIS AND ACTIVITY OF ABSCISIC ACID ANALOGUES FOR PROBING RECEPTORS FOR ABSCISIC ACID

用于探测脱落酸受体的脱落酸类似物的合成和活性

基本信息

批准号：
07660136
负责人：
HIRAI Nobuhiro
金额：
$ 1.79万
依托单位：
KYOTO UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
1995
资助国家：
日本
起止时间：
1995 至 1996
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-07660136/
关键词：
Abscisic acid ABA Conformation フッ素化

项目摘要

Abscisic acid (ABA) is an unique hormone protecting plants from environmental stresses. Analogues of ABA were synthesized to investigate the interaction between ABA and receptors.(1) Role of the hydroxyl groups. The activity of 1'-deoxy-1'-fluoro-and 1'-deoxy-ABAs suggested that the 1'-hydroxyl group may interact with the receptor by means of an uncharged hydrogen bond. The activity of 8'-fluoro-ABA suggested that the 8'-hydroxyl group of 8'-hydroxy-ABA does not affect the acitivity of ABA,meaning that the activity of highly labile 8'-hydroxy-ABA is as strong as that of (+) -ABA.(2) Examination of the pseudo-symmetry of ABA.7'-, 8'-and 9'-Methyl-, and 7'-, 8'-and 9'-ethyl analogues of ABA,whose pseudo-symmetry is decreased, were synthesized. The correlation of the decrease in the activity of (-) -7'-and 9'-alkyl-ABAs with that of (+) -9'-and 7'-alkyl-ABAs, respectively, seemed to agree with the hypothesis. The activity of the 8'-alkyl-ABAs indicated that the activity was relatively unaffected by the bulky group at C-8' of (+) -ABA.Alkylation of C-8' and C-9', especially that of C-8', of (-) -ABA markedly reduced the activity. C-8' of (-) -ABA would occupy the space facing the re-face of C-2' in natural (+) -ABA.The low activity of (-) -8'-alkyl-ABA suggests the presence of a strict steric requirement of the binding sites to occupy the re-face of C-2' in (+) -ABA.(3) The active conformation The cyclopropane analogues and the achiral cyclohexadienone analogue of ABA were designed, and synthesized. The activiti of these analogues suggested that the axial substituent at the beta-side of the ring is fatal to the activity. The active conformation of abscisic acid would be a conformation where C-9' is equatorial and the side chain is between pseudo-axial and bisectional, that is, close to the favored half-chair with the side chain pseudo-axial rather than the less favored half-chair with the side chain pseudo-equatorial.

脱落酸 (ABA) 是一种独特的激素，可以保护植物免受环境压力。合成ABA类似物来研究ABA与受体之间的相互作用。(1)羟基的作用。 1'-脱氧-1'-氟-和1'-脱氧-ABA 的活性表明1'-羟基可以通过不带电荷的氢键与受体相互作用。 8'-氟-ABA的活性表明8'-羟基-ABA的8'-羟基不影响ABA的活性，这意味着高度不稳定的8'-羟基-ABA的活性与8'-羟基-ABA一样强。 (+) -ABA。 (2) ABA.7'-、8'-和9'-甲基-以及7'-、8'-和9'-乙基的伪对称性检验合成了假对称性降低的ABA类似物。 (-) -7'-和9'-烷基-ABA 活性下降分别与(+) -9'-和7'-烷基-ABA 活性下降的相关性似乎与假设一致。 8'-烷基-ABA的活性表明，该活性相对不受(+)-ABA C-8'处大基团的影响。C-8'和C-9'的烷基化，特别是C-的烷基化(-)-ABA的8'，显着降低了活性。 (-) -ABA 的 C-8' 将占据天然 (+) -ABA 中 C-2' 面对面的空间。 (-) -8'-烷基-ABA 的低活性表明存在(3)活性构象设计并合成了ABA的环丙烷类似物和非手性环己二烯酮类似物。这些类似物的活性表明环β侧的轴向取代基对该活性是致命的。脱落酸的活性构象是C-9'处于赤道且侧链介于伪轴和二等分之间的构象，即接近于侧链伪轴的半椅而不是较小的侧链。偏爱侧链伪赤道的半椅。