67587-21-7Relevant academic research and scientific papers
Synthesis of Bungeanool, Isobungeanool, Dihydrobungeanool, Tetrahydrobungeanool, Hazaleamide, Lanyuamide III, and Analogues
Loo, Ying-Hui,Leakasindhu, Suleeporn,Kan, Chi-Ming,Toy, Patrick H.
, p. 1145 - 1156 (2021/11/09)
The bungeanools are a family of alkamide natural products isolated from the pericarps of Zanthoxylum bungeanum (Sichuan pepper), and they are structurally related to the sanshools. While the sanshools, especially hydroxy-?-sanshool, have been studied in a variety of contexts, research regarding the bungeanools has been much more limited. To facilitate their study, we have developed stereoselective syntheses of all four members of this family of compounds by using flexible routes that are also amenable to the synthesis of analogues. The key transformation in the syntheses was the stereoselective triphenylphosphine/ phenol-catalyzed isomerization of an alkynoate to the corresponding conjugated E,E-dienoate.
Synthesis of gem-dideuterated tetradecanoic acids and their use in investigating the enzymatic transformation of (Z)-11-tetradecenoic acid into (E,E)-10,12-tetradecadienoic acid
Rodriguez, Sergio,Camps, Francisco,Fabrias, Gemma
, p. 8052 - 8058 (2007/10/03)
We report the preparation of the deuterated tetradecanoic acids [2,2,3,3-2H4]-, [2,2,3,3,10,10-2H6]-, and [2,2,3,3,13,13-2H6]-tetradecanoic acids (1, 2, and 3, respectively) and their use to investigate the mechanism of the enzymatic transformation of (Z)-11-tetradecenoic acid into (E,E)-10,12-tetradecadienoic acid. Probes 2 and 3 were prepared from intermediate ketones 7 and 10, which were transformed into the labeled bromides 17 and 18 by reduction with NaBD4, tosylation of the resulting alcohol, replacement of the tosyloxy group by deuteride with LiAlD4, hydrolysis, and reaction with N-bromosuccinimide. The resulting bromides were converted into the α-acetylenic esters 21 and 22, respectively, and the additional deuterium labels were introduced by reduction of the conjugated triple bond with Mg in deuterated methanol. The same sequence of reactions starting with 11-bromoundecane afforded 27. Saponification of the labeled esters 23, 24, and 27 gave the deuterated acids 2, 3, and 1, respectively. The results of the biochemical experiments showed that C10-H removal, but not elimination of C13-H, was sensitive to deuterium substitution in the transformation of (Z)-11-tetradecenoic acid into (E,E)-10,12-tetradecadienoic acid, which is consistent with the hypothesis that this desaturase reaction involves a first slow, C10-H bond cleavage, with probable formation of an unstable allylic intermediate, followed by a second fast C13-H bond removal and concomitant rearrangement.
Synthesis of Anacardic Acids
Zehnter, Reinhard,Gerlach, Hans
, p. 2209 - 2220 (2007/10/03)
The anacardic acids 1-11, isolated from various plants, were synthesized by a new general method.Reaction of the methyl alkynoates 12-18 with 1-methoxy-1,4-cyclohexadiene at 200 deg C afforded directly the methyl 2-methoxybenzoates 19-25 with long chain substituents in 6-position in 74-85percent yield.The dienophiles 12-16 were prepared by pyrolysis of the corresponding acylphosphoranes 26-30, the dienophiles 17 and 18 by methoxycarbonylation of the corresponding alkynes 31 and 32 via the hydroxy esters 33 and 34.Demethylation of 19-23 with AlI3 gave the methyl salicylates 35-39 which could be hydrolized to the anacardic acids 1-4 and 7.Hydrolysis of 24 and 25 provided the hydroxy acids 40 and 41, which were converted by treatment with CBr4/PPh3 into the acids 42 and 43 bearing bromoalkyl side chains.These were transformed into 44-47 by reaction with 1-hexynyllithium and 1-octynyllithium.Stereoselective hydrogenation of 44-47 gave 48-51 with (Z)-alkene side chains.In a similar approach 42 was converted into 52 and then into 53, which gave upon treatment with 1-pentynylmagnesium bromide or 1-heptynylmagnesium bromide the acids 54 and 55 with alkadiyne side chains.Stereoselective hydrogenation provided 56 and 57 with (Z,Z)-alkadiene side chains.The 2-methoxy group in 48-51, 56, 57 was demethylated by treatment with AlI3 to give the anacardic acids 5, 6, 8-11. - Keywords: Anacardic acids; Benzoates, methyl 6-alkyl-2-methoxy-; 2-Alkynoates, methyl; Aluminium triiodide, demethylation by treatment with
