Refernces
10.1007/BF00568510
The research investigates the reductive amination of l-menthol using aliphatic nitriles, aiming to understand the stereochemical composition of the products and propose a mechanism for the reaction. The study utilized a copper-alumina catalyst modified with lithium hydroxide and conducted the reaction under specific conditions of temperature, pressure, and space velocity. The chemicals involved included l-menthol, aliphatic nitriles such as acetonitrile, acrylonitrile, and butyronitrile, and a catalyst composed of 15% copper and 6% lithium hydroxide on alumina. The results showed that the reaction produced a mixture of isomeric optically active N-alkyl derivatives of menthylamine, neomenthylamine, isomenthylamine, and neoisomenthylamine in a ratio of 54:24:17:5.
10.3390/10010081
The research investigates the use of hydrolytic enzymes, specifically a lipase from Candida cylindracea and a cutinase from Fusarium solani pisii, in the selective cleavage of ester groups on the peripheral layer of linear and branched polyamides conjugated to fragrances citronellol and L-menthol via ester linkages. The study explores the potential of these enzymes for post-synthetic modification of dendrimers and hyperbranched molecules. The polyamides were synthesized in a convergent fashion, and the hydrolysis studies were conducted in aqueous buffered systems under optimal conditions for the enzymes. Analytical techniques such as RP-HPLC, GC, and MALDI-TOF mass spectrometry were employed to monitor the alcohol release and identify hydrolytic products. The results revealed that the enzyme's ability to interact with the substrates decreased significantly with increased branching density, rigidity, and bulkiness of the polyamide-fragrance conjugates. The lipase showed limited efficacy, with notable ester cleavage only observed in one case, while the cutinase demonstrated more favorable interactions, particularly with linear polyamides.
10.1016/S0040-4039(00)73532-5
The study explores innovative synthetic pathways for the production of (+)-Artemisinin, a sesquiterpene endoperoxide with significant antimalarial properties derived from traditional Chinese medicine. The researchers utilized (-)-menthol as the starting material and developed two synthetic routes involving key steps such as OH-assisted chemo- and stereoselective C-H functionalization and acid/base-induced ring opening. The synthesis involved several intermediate compounds, including enone 14, epoxide 15, secondary alcohol 16, and keto-alcohol 17, which were characterized using spectroscopic methods. The study successfully synthesized two useful precursors, (+)-artemisiol (2) and compound 5, which can be further converted into (+)-Artemisinin. The chemical transformations included Jones oxidation, acetylation, reduction, oxidation, and benzylation steps, among others. The study's innovative approach to C-H functionalization and ring opening provides valuable insights for the total synthesis of (+)-Artemisinin and its analogues, contributing to the global efforts in malaria treatment.
Xi
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