23444-68-0Relevant academic research and scientific papers
The Structure of Isoaplysin, a Brominated Rearranged Cuparane-Type Sesquiterpenoid from the Red Alga Laurencia okamurai Yamada
Suzuki, Minoru,Kurata, Kazuya,Kurosawa, Etsuro
, p. 3981 - 3982 (1986)
The structure of isoaplysin isolated from the red alga Laurencia okamurai Yamada has been established by the spectral and chemical methods.
The total synthesis of (-)-aplysin via a lithiation-borylation- propenylation sequence
Fletcher, Catherine J.,Blair, Daniel J.,Wheelhouse, Katherine M.P.,Aggarwal, Varinder K.
, p. 7598 - 7604 (2012/09/21)
A concise, highly enantioselective synthesis of sesquiterpene natural products (-)-debromoaplysin and (-)-aplysin has been completed. The key steps included lithiation-borylation of a secondary benzylic carbamate to give a tertiary boronic ester followed by propenylation which installed the quaternary stereocenter with complete enantioselectivity. Subsequent RCM followed by deprotection and in situ cyclization led to debromoaplysin with good diastereoselectivity from which the target compound was prepared in just eight overall steps.
A Remarkable Substituent Effect on the Enantioselectivity of Tandem Asymmetric Epoxidation and Enantiospecific Ring Expansion of Cyclopropylidene Alcohols: A New Enantiocontrolled Synthesis of (-)-Debromoaplysin and (-)-Aplysin
Nemoto, Hideo,Nagamochi, Masatoshi,Ishibashi, Hiroki,Fukumoto, Keiichiro
, p. 74 - 79 (2007/10/02)
A remarkable substituent effect by the tert-butyldimethylsiloxy group on the enantioselectivity of the tandem asymmetric epoxidation and enantiospecific ring expansion of 2--2-cyclopropylideneethanol (18), affording (S)-(-)-2--2-hydroxymethylcyclobutanone (21) in high yield and high enantiomeric excess, was observed.This enabled us to accomplish a concise and highly enantioselective total synthesis of (-)-debromoaplysin (2) and (-)-aplysin (1), providing a new and general strategy for the enantioselective synthesis of biologically important substances having the dihydrobenzofuran framework.
ENANTIOCONTROLLED SYNTHESES OF THE CUPARENE SESQUITERPENES, (-)-HERBERTENE, (+)-β-CUPARENONE, (-)-DEBROMOAPLYSIN, AND (-)-APLYSIN
Takano, Seiichi,Moriya, Minoru,Ogasawara, Kunio
, p. 329 - 332 (2007/10/02)
Enantiocontrolled syntheses of the Cuparene sesquiterpenes, (-)-herbertene, (+)-cuparenone, (-)-debromoaplysin, and (-)-aplysin, have been achieved starting from the optically active tricyclic dienone by employing a Fischer indolization reaction under non-acidic conditions as the key step.
Total Synthesis of (-)-Aplysin and (-)-Debromoaplysin
Ronald, Robert C.,Gewali, Mohan B.,Ronald, Bruce P.
, p. 2224 - 2229 (2007/10/02)
The total synthesis of optically active (-)-aplysin (1) and (-)-debromoaplysin (2) employing novel (isopinocampheyloxy)methyl ethers for phenolic hydroxyl protection and diastereomeric resolution is described.A key transformation is the unusual cyclization of the diastereomeric chlorohydrins 12 and 13 in methanolic base to form the enantiomeric tricyclic alcohols (-)-16 and (+)-16 with cleavage of the acetal-linked (isopinocampheyloxy)methyl resolving/protecting group.This transformation was followed by substitution of the tertiary hydroxyl via the derived chloride with a methyl group by Grignard coupling with methylmagnesium bromide.The methyl insertion occurred with retention of configuration and resulted in formation of the natural aplysin system from 12 in just three steps.The conversion of the methylated tricyclic ether 20 to (-)-debromoaplysin (2) was accomplished in two steps by double bond isomerization and selective reduction.Bromination of (-)-2 afforded (-)-aplysin (1).
