126783-82-2Relevant academic research and scientific papers
Easy preparation of methyl 7-epi-jasmonate and four stereoisomers of methyl cucurbate, and assessment of the stereogenic effect of jasmonate on phytohormonal activities
Seto, Hideharu,Nomura, Emi,Fujioka, Shozo,Koshino, Hiroyuki,Suenaga, Toshiro,Yoshida, Shigeo
, p. 361 - 367 (1999)
To test the stereogenic effect of jasmonate on phytohormonal activities, methyl 7-epi-jasmonate (1b) and four stereoisomers of methyl cucurbate were easily prepared in racemic form: epimerization at the C-7 position of a commercially available methyl jasmonate (2b) with a base and subsequent fractional distillation gave a 46:54 mixture of 1b and 2b, whose reduction gave a mixture of methyl cucurbates (3-6). This synthetic chemistry was supplemented by molecular modeling and an NMR study on 1b and 2b. An assessment of the inhibitory activities of the prepared jasmonates on growth of the second leaf sheath of rice and on seed germination of cress clarified that the cis-configuration of the C-3 and C-7 side chains of jasmonate was an important factor for the high activities. In inhibiting the seed germination of cress, methyl 6-epi-cucurbate (4) exhibited activity that was markedly higher than the other compounds tested, showing that the stereochemistry at C-6 as well as at C-3 and C-7 was strictly recognized by this bioassay.
Stereoselective synthesis of epi-jasmonic acid, tuberonic acid, and 12-oxo-PDA
Nonaka, Hisato,Ogawa, Narihito,Maeda, Noriaki,Wang, Yong-Gang,Kobayashi, Yuichi
experimental part, p. 5212 - 5223 (2010/12/25)
epi-Jasmonic acid (epi-JA) and tuberonic acid (TA) were synthesized from the key aldehyde, all cis-2-(2-hydroxy-5-vinylcyclopentyl)acetaldehyde (14), which was in turn prepared stereoselectively from the (1R)-acetate of 4-cyclopentene-1,3-diol (10) through SN2-type allylic substitution with CH2CHMgBr followed by Mitsunobu inversion, Eschenmoser-Claisen rearrangement, and regioselective Swern oxidation of the corresponding bis-TES ether (13). Wittig reaction of the aldehyde 14 with [Ph3P(CH 2)Me]+Br- followed by oxidation afforded epi-JA (3) stereoselectivity over the trans isomer. Similarly, TA (5) was synthesized. Furthermore, the above findings were applied successfully to improve the total efficiency of the previous synthesis of 12-oxo-PDA (1).
Chemistry and Stereochemistry of Iridoids, XIII. - Synthesis of Enantiomerically Pure Methyl (1R,2S,2''Z)-(+)-Jasmonate Starting from Catalpol
Weinges, Klaus,Lernhardt, Ulrich
, p. 751 - 754 (2007/10/02)
Enantiomerically pure methyl (1R,2S,2''Z)(+)-jasmonate (2), which was recognized as a component of the fragrance of the jasmine flower oil, was synthesized starting from catalpol (3). 2 is easily epimerized to 1.Thus, it is necessary to use very mild conditions in the course of the synthesis and purification.These results raise the question whether 2 exists as a natural product in the flower of jasmine and 1 arises during the isolation.
