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N-(17-Phosphonooxylinolenoyl)glutamine (1) and N-(17-phosphonooxylinoleoyl)glutamine (2) were isolated from the regurgitate of Spodoptora exigua and identified as the first natural alkyl chain-phosphorylated fatty acid derivatives. The compounds were characterized by HPLC-MS/MS and the assigned structures confirmed by synthesis via a dissymmetric bis-Wittig approach as the key reaction. Rearing of the larvae on a diet enriched with inorganic phosphate increased the amount of the phosphorylated N-acyl glutamines in the regurgitate. 相似文献
4.
Flowers of Jasminum rincospernum convert deuterium-labeled jasmonic acid [2H5]- 4a and methyl 1,2-didehy-drojasmonate [2H4]- 8 into labeled cis-jasmone [2H4]- 1. The labeling pattern of the resulting cis-jasmone ( 1 ) is consistent with a Grob fragmentation of the didehydrojasmonic acid 8a by decarboxylation after protonation of the keto group. The pathway is also operative in leaves of several higher plants, including mono- and dicotyledonous specimens. In Lima beans besides cis-jasmone ( 1 ) an equimolar mixture of trans- and cis-isomers of methyl jasmonate ( 4 ) and epi- 4 , is emitted after treatment with Jasmonic acid ( 4a ). The relative ratio of 1 and 4 /epi- 4 is critically dependent on the concentration of the administered jasmonic acid ( 4a ) and the ambient temperature of the plant. Unlike 4a , the 1,2-didehydrojasmonic acid ( 8a ) is not able to induce volatile biosynthesis. Therefore, the transformation of 4a via 8 a into 1 appears to have a special importance for the irreversible inactivation and disposal of the plant stress hormone jasmonic acid to the gas phase and may serve, besides other modes of inactivation, as a shunt in case of high internal of the stress hormone 4a. The conversion of the biologically active jasmonic acid ( 4a ) into the inactive and volatile cis-jasmone (1) is the first example of a disposal of an inactive metabolite of a phytohormone to the gas phase as an infinite sink. 相似文献
5.
Desmarestene 1 6-(1Z,3-butadienyl)-1,4-cycloheptadiene and viridiene 3 cis-3-(1Z, 3-butadienyl)-4-vinylcyclopentene are chemical messengers for male gametes of the brown algae Desmarestia aculeate and Desmarestia viridis. Total syntheses of 1 , 3 and their stereoisomers 1a , 3a - c are reported. Gas-chromatographic comparison of synthetic 1 and 3 with the corresponding natural products has established their structural identity. 相似文献
6.
Structural modifications of multifidene ( 1 ), viridiene ( 2 ) and ectocarpene ( 5 ) led to the synthesis of eleven new pheromone components or imitatin substances mostly by Grignard alkylation of cyclopentene and cycloheptadiene synthons. A new lactone α,ω dienol conversion is reported. 相似文献
7.
Chiral [2H] -labelled methylene groups flanked by two double bonds within (poly)unsaturated fatty acids are readily available from trans-2,3-epoxy[2,3-2H2] alk-4-yn-l-ols, obtained in their turn by asymmetric epoxidation of the corresponding (E)-[2,3-2H2] alk-2-en-4-yn-l-ols (see Scheme 3). The procedure is exemplified for (8S,3Z,6Z,9Z)-[7,8-2H2] trideca-3,6,9-trienoic acid ((8S)- 11 ) and (8R)- 11 (Scheme 4) as well as for (5S,3Z,6Z)-[4,5?2H2]deca-3,6-dienoic acid ((5S)- 13 ) and (5R)- 13 (Scheme 5). 相似文献
8.
Wilhelm Boland Nora Schroer Christiane Sieler Martin Feigel 《Helvetica chimica acta》1987,70(4):1025-1040
Giffordene (=(2Z,4Z,6E,8Z)-2,4,6,8-undecatetraene; 9f ) and five steroisomers are new C11H16 hydrocarbons from the marine brown alga Giffordia mitchellae. Their synthesis is based on non-stereoselective Wittig reactions of (E)-2-alkenals with appropriate acetylenic phosphoranes and subsequent chromatographic separation of the resulting (E/Z)-pairs. The uniform enynes (>98% purity) are then stereospecifically reduced to (Z)-alkenes with Zn(Cu/Ag) in aq. MeOH at r.t. 13C- and 1 H-NMR data of the new tetraenes are presented. Biosynthetically, giffordene ( 9f ) originates from dodeca-3,6,9-trienoic acid via an unstable (3Z,5Z,8Z)-1,3,5,8,-undecatetraene followed by a thermally allowed antarafacial 1,7-sigmatropic hydrogen shift to the (2Z,4Z,6E,8Z)-isomer 9f . 相似文献
9.
Philip J. Boland 《Arkiv f?r Matematik》1977,15(1-2):87-91
LetU be an open subset of a complex locally convex spaceE, andH(U) the space of holomorphic functions fromU toC. If the dualE′ ofE is nuclear with respect to the topology generated by the absolutely convex compact subsets ofE, then it is shown thatH(U) endowed with the compact open topology is a nuclear space. In particular, ifE is the strong dual of a Fréchet nuclear space, thenH(U) is a Fréchet nuclear space. 相似文献
10.
Boland NA Casey M Hynes SJ Matthews JW Smyth MP 《The Journal of organic chemistry》2002,67(11):3919-3922
A novel procedure for the preparation of enantiopure 1,4-disubstituted 2-imidazolines is reported. Enantiopure beta-amino alcohols are converted into N-hydroxyethylamides, which are reacted with excess thionyl chloride, or with thionyl chloride followed by phosphorus pentachloride to yield N-chloroethylimidoyl chlorides. These intermediates are treated with amines and anilines to produce N-chloroethylamidines, which are converted into imidazolines upon workup with aqueous hydroxide. The method is simple and efficient and has been used to prepare a wide variety of enantiopure imidazolines, in a modular fashion, from readily available amino alcohols. 相似文献