4529-04-8Relevant articles and documents
Total Synthesis of (+)-Arborisidine
Zhou, Zhiyao,Gao, Alison X.,Snyder, Scott A.
, (2019)
The first total synthesis of arborisidine, a unique Kopsia indole alkaloid possessing a fully substituted cyclohexanone ring system with two quaternary carbons, has been achieved in seven steps in racemic format from tryptamine and in nine steps in asymmetric format from d-tryptophan methyl ester. Key elements of the design include a carefully orchestrated decyanation protocol to finalize the asymmetric formation of an aza-quaternary center that is challenging to access in optically active format via direct Pictet-Spengler cyclizations with tryptamine, a metal-promoted 6-endo-dig cyclization of an enyne to establish the second core quaternary center, and regiospecific functionalizations of the resultant complex diene to finalize the target structure. The distinct and efficient nature of the developed solution is highlighted by several unsuccessful approaches and unexpected rearrangements.
Sequential Norrish type II photoelimination and intramolecular aldol cyclization of α-diketones: Synthesis of polyhydroxylated cyclopentitols by ring contraction of hexopyranose carbohydrate derivatives
Alvarez-Dorta, Dimitri,Leon, Elisa I.,Kennedy, Alan R.,Martin, Angeles,Perez-Martin, Ines,Riesco-Fagundo, Concepcion,Suarez, Ernesto
supporting information, p. 10312 - 10333 (2013/09/02)
The excitation of the innermost carbonyl of nono-2,3-diulose derivatives by irradiation with visible-light initiates a sequential Norrish type II photoelimination and aldol cyclization process that finally gives polyfunctionalized cyclopentitols. The rearrangement has been confirmed by the isolation of stable acyclic photoenol intermediates that can be independently cyclized by a thermal 5-(enolexo)-exo-trig uncatalyzed aldol reaction with high diastereoselectivity. In this last step, the large deuterium kinetic isotope effect found for the 1,5-hydrogen atom transfer seems to indicate that the aldol reaction runs through a concerted pericyclic mechanism. Owing to the ready availability of pyranose sugars of various configurations, this protocol has been used to study the influence of pyranose ring-substituents on the diastereoselectivity of the aldol cyclization reaction. In contrast with other pyranose ring contraction methodologies no transition-metal reagents are needed and the sequential rearrangement occurs simply by using visible light and moderate heating (0 to 60 °C). Copyright
Novel aliphatic compounds, process for their preparation and their usage
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Page/Page column 17-18, (2010/02/05)
The present invention provides an aliphatic compound represented by the following formula (I) or pharmacologically acceptable salts thereof: where n denotes an integer of 1 to 11, and 1 denotes an integer of 1 to 16, the aliphatic compound being an optical isomer of the (2R,3S,2′S) configuration when the 8-position thereof is a double bond, or an optical isomer of the (2S,3R,2′RS) configuration when the 8-position is a single bond; methods for producing the compound or pharmacologically acceptable salts thereof; and uses of the compound in the treatment of cardiovascular diseases (e.g. arteriosclerosis, cardiac diseases), cancer, rheumatism, diabetic retinopathy, and respiratory diseases.
