109307-91-7Relevant academic research and scientific papers
A formal total synthesis of (-)-brevisamide, a marine monocyclic ether amide
Lee, Jungmee,Oh, Hong-Se,Kang, Han-Young
, p. 1099 - 1102 (2015/02/19)
A formal total synthesis of (-)-brevisamide, a monocyclic ether amide with architecturally unique structural features, has been achieved. The tetrahydropyran core part of the target was synthesized by the aldol reaction followed by ring-closing metathesis using the Grubbs second generation catalyst. After the stereochemistry at the carbon center bearing the hydroxy group was adjusted, the carbon-carbon double bond was stereoselectively reduced by catalytic hydrogenation. Finally, introduction of the amino group was followed by acetylation, which provided the desired advanced intermediate.
A formal stereoselective synthesis of (-)-brevisamide
Yadav,Raju,Ravindar,Subba Reddy
, p. 3227 - 3229 (2013/06/27)
An efficient stereoselective formal synthesis of marine derived monocyclic ether (-)-brevisamide is reported. The key steps involved in this synthesis are syn-Aldol reaction, Sharpless asymmetric epoxidation, and stereoselective construction of tetrahydropyran ring by 6-endo-cyclization of suitably substituted hydroxy styrylepoxide.
Total Syntheses of (+)-Thyrsiferol, (+)-Thyrsiferyl 23-Acetate, and (+)-Venustatriol
Hashimoto, Masaru,Kan, Toshiyuki,Nozaki, Koji,Yanagiya, Mitsutoshi,Shirahama, Harushia,Matsumoto, Takeshi
, p. 5088 - 5107 (2007/10/02)
The first total syntheses of (+)-thyrsiferol (1), (+)-thyrsiferyl 23-acetate (3), and (+)-venustatriol (5) have been accomplished in a stereoselective manner.An effective synthetic scheme to construct the BC ring system, which adopts a chair/twist-boat conformation, was first developed by means of a model study.This method involves stereoselective formation of the strained C ring by intramolecular attack of the C7-hydroxyl group at the C3-postion of the 2,3-epoxy alcohol, employing titanium tetraisopropoxide as an acidic activator.Based on the information accumulated in the model study and retrosynthetic considerations, the total syntheses of 1,3, and 5 were performed in the sequence of (1) construction of the BC ring system equipped with a C1-C6 carbon unit, (2) elongation of the C17-C24 carbon chain, (3) formation of a D ring through the stereoselective epoxidation of the 4-en-1-ol system and successive cyclization, and (4) construction of the A ring by bromonium ion induced cyclization of the 4-en-1-ol system.
New Approaches to the Synthesis of Vitamin D Metabolites. 2. The Effect of Some Substituents on Stereochemistry in the Intramolecular Cycloadditions of Nonatrienes
Parker, Kathlyn A.,Iqbal, Tahir
, p. 4369 - 4377 (2007/10/02)
Intramolecular Diels-Alder reactions of 8-methyl-1,3,8-nonatrienes 5 and 6 were studied to determine the effects of substituents on the stereochemistry of ring closure.Substituents at C-3 favor closure to trans-hydrindenes; likewise, a C-7 alkyl group favors closure to trans-hydrindene products.Substrates bearing a C-7 alkyl substituent afforded products in which the alkyl substituent was invariably cis to the angular methyl group (34 and 35).The ratio of trans:cis fused hydrindenes was shown to be solvent-dependent; yields were improved when closures were effected in dimethylaniline.
