96555-02-1Relevant articles and documents
Preparation method of optically active menthol
-
Paragraph 0040; 0047-0049, (2021/03/31)
The invention provides a preparation method of optically active menthol, wherein the preparation method comprises the following steps: 1) carrying out alkali pretreatment on a compound A (methyl 5-methyl-4-hexenoate), and cyclizing with ethyl acetoacetate under the action of a copper salt chiral phosphine catalyst to generate a compound B (methyl isomenthodienone-4-formate); 2) carrying out a decarboxylation reaction on the compound B under the action of alkali to generate a compound C (isomenthodienone); 3) reducing the compound C under the action of a catalyst to generate a compound D (isomenthyl dienol); and 4) hydrogenating the compound D under the action of chiral induction and a catalyst to generate the optically active menthol. The preparation method disclosed by the invention has the advantages of novel reaction route, readily available raw materials, low price and mild reaction conditions, and is suitable for industrial production.
Using (+)-carvone to access novel derivatives of (+)-ent-cannabidiol: The first asymmetric syntheses of (+)-ent-CBDP and (+)-ent-CBDV
Golliher, Alexandra E.,Tenorio, Antonio J.,Dimauro, Nina O.,Mairata, Nicolas R.,Holguin, F. Omar,Maio, William
supporting information, (2021/02/20)
(?)-Cannabidiol [(?)-CBD] has recently gained prominence as a treatment for neuro-inflammation and other neurodegenerative disorders; interest is also developing in its synthetic enantiomer, (+)-CBD, which has a higher affinity to CB1/CB2 receptors than the natural stereoisomer. We have developed an inexpensive, stereoselective route to access ent-CBD derivatives using (+)-carvone as a starting material. In addition to (+)-CBD, we report the first syntheses of (+)-cannabidivarin, (+)-cannabidiphorol as well as C-6/C-8 homologues.
Enantiospecific Total Syntheses of (+)-Hapalindole H and (?)-12-epi-Hapalindole U
Dethe, Dattatraya H.,Das, Saikat,Kumar, Vijay B.,Mir, Nisar A.
supporting information, p. 8980 - 8984 (2018/06/04)
Enantiospecific total syntheses of (+)-hapalindole H and (?)-12-epi-hapalindole U as well as the formal syntheses of (+)-hapalindole Q and (+)-12-epi-fischerindole U isothiocyanate have been described. Key steps of our approach feature expedient, highly regio- and diastereoselective Lewis acid catalyzed Friedel–Crafts reaction of indole with cyclic allylic alcohols and intramolecular reductive Heck reaction. Efficiency of the synthetic route also relies on an alkynyl aluminate complex driven regioselective nucleophilic epoxide opening from a sterically hindered site.
Chemoenzymatic Synthesis of the Intermediates in the Peppermint Monoterpenoid Biosynthetic Pathway
Cheallaigh, Aisling Ní,Mansell, David J.,Toogood, Helen S.,Tait, Shirley,Lygidakis, Antonios,Scrutton, Nigel S.,Gardiner, John M.
, p. 1546 - 1552 (2018/08/04)
A chemoenzymatic approach providing access to all four intermediates in the peppermint biosynthetic pathway between limonene and menthone/isomenthone, including noncommercially available intermediates (-)-trans-isopiperitenol (2), (-)-isopiperitenone (3), and (+)-cis-isopulegone (4), is described. Oxidation of (+)-isopulegol (13) followed by enolate selenation and oxidative elimination steps provides (-)-isopiperitenone (3). A chemical reduction and separation route from (3) provides both native (-)-trans-isopiperitenol (2) and isomer (-)-cis-isopiperitenol (18), while enzymatic conjugate reduction of (-)-isopiperitenone (3) with IPR [(-)-isopiperitenone reductase)] provides (+)-cis-isopulegone (4). This undergoes facile base-mediated chemical epimerization to (+)-pulegone (5), which is subsequently shown to be a substrate for NtDBR (Nicotiana tabacum double-bond reductase) to afford (-)-menthone (7) and (+)-isomenthone (8).
Protecting group free enantiospecific total syntheses of structurally diverse natural products of the tetrahydrocannabinoid family
Dethe, Dattatraya H.,Erande, Rohan D.,Mahapatra, Samarpita,Das, Saikat,Kumar B., Vijay
supporting information, p. 2871 - 2873 (2015/03/03)
A simple, highly diastereoselective, Lewis acid catalyzed Friedel-Crafts coupling of a cyclic allylic alcohol with resorcinol derivatives has been developed. The method was applied for the enantiospecific total syntheses of structurally diverse natural products such as machaeriol-D, Δ8-THC, Δ9-THC, epi-perrottetinene and their analogues. Synthesis of both natural products and their enantiomers has been achieved with high atom economy, in a protecting group free manner and in less than 6 steps, the longest linear sequence, in a very good overall yield starting from R-(+) and S-(-)-limonene.
Enantiospecific total syntheses and assignment of absolute configuration of cannabinol-skeletal carbazole alkaloids murrayamines-O and -P
Dethe, Dattatraya H.,Das, Saikat,Dherange, Balu D.,Mahapatra, Samarpita
supporting information, p. 8347 - 8350 (2015/06/02)
First enantiospecific total syntheses of the cannabinol-skeletal carbazole alkaloids murrayamines-O and -P isolated from root barks of Murraya euchrestifoli, have been accomplished by highly diastereoselective, Lewis acid catalyzed coupling reactions of commercially available monoterpenes with carbazole derivative, which in addition to confirming the structure also established the absolute configuration of the natural products. Synthesis of both natural products and their enantiomers was achieved with high atom economy, in a protecting-group free manner and in six steps longest linear sequence from commercially available aniline derivative and verbenol.
3-Alkyl-p-menthan-3-ol derivatives: synthesis and evaluation of their physiological cooling activity
Fuganti, Claudio,Joulain, Daniel,Maggioni, Francesco,Malpezzi, Luciana,Serra, Stefano,Vecchione, Andrea
body text, p. 2425 - 2437 (2009/04/06)
Different 3-alkyl-p-methan-3-ol derivatives provide a strong physiological cooling effect with potential application as food and cosmetic additives. In order to investigate the influence of the chemical structure on the cooling sensation, the stereoselective syntheses of 29 different 3-alkyl-p-methan-3-ol derivatives were accomplished. All the compounds obtained are odorless and were evaluated by taste, considering two sensations: a cooling effect and bitterness. The results of this structure-activity relationship study highlight that compounds with a (1R,4S)-configuration are the isomers with the more intense cooling effect and lower bitterness. In addition, the structure of the 3-alkyl chain affected the latter properties. Increasing the chain length over two carbon atoms does not change the cooling power, but enhances the bitterness with the additional feature that the branched isomers are considerably more bitter than the linear ones. Overall, the 3-alkyl-p-menthan-3-ol isomers with the best quality in terms of high cooling power and low bitterness are (1R,4S)-3-(hydroxymethyl)-p-menthan-3-ol diastereoisomers (-)-38 and (-)-42.
Planar chiral cyclic ether: Asymmetric resolution and chirality transformation
Tomooka, Katsuhiko,Komine, Nobuyuki,Fujiki, Daisuke,Nakai, Takeshi,Yanagitsuru, Syun-Ichi
, p. 12182 - 12183 (2007/10/03)
Remarkably stable planar chirality was found in a nine-membered diallylic cyclic ether. Enantiomerically enriched ether was prepared by a kinetic resolution of a racemic one, which is valuable as a novel type of chiral building block. Copyright
Lipase-catalyzed resolution of p-menthan-3-ols monoterpenes: Preparation of the enantiomer-enriched forms of menthol, isopulegol, trans- and cis-piperitol, and cis-isopiperitenol
Serra, Stefano,Brenna, Elisabetta,Fuganti, Claudio,Maggioni, Francesco
, p. 3313 - 3319 (2007/10/03)
A study on the enzymic resolution of the most common p-menthan-3-ol monoterpene isomers is described. Enantioenriched alcohols 1, 5, 10, 11 and 12 are obtained by means of the lipase-mediated kinetic acetylation of the corresponding racemic materials. The stereochemical aspects of the enzymic process have been investigated. We found that the structural features of the starting p-menthan-3-ol as well as the kind of lipase used, impacted strongly on the enantioselectivity of the resolution. The potentialities of this approach for preparative purposes are discussed.
