An efficient enzymatic preparation of (+)- and (−)-conduritol E, a cyclitol with C2 symmetry
摘要:
Lypozyme(R) IM (immobilised lipase from Mucor miehei) catalyses the enantiomeric alcoholysis of tetraacetylconduritol E (+/-)-2 to give enantiopure (1R,2R,3R,4R)-tetrahydroxycyclohex-5-ene (-)-1, and the unreacted ester (1S,2S,3S,4S)-tetraacetyloxycyclohex-5-ene, (+)-2. The latter was transformed by basic hydrolysis into (+)-1 in high yield and 95% ee. Selective amination of partial ester (-)-3, obtained by short alcoholysis of (+/-)-2, furnished the previously unreported conduramine F-4, (-)-4. (C) 1997 Published by Elsevier Science Ltd.
作者:William T. Lambert、Gregory H. Hanson、Farid Benayoud、Steven D. Burke
DOI:10.1021/jo051479m
日期:2005.11.1
steps and 4% overall yield. In a separate route, 7 was also synthesized in 18 steps and 2% overall yield from a derivative of α-d-glucoheptonic acid γ-lactone (62). While the former route installs the fully elaborated C-ring endowed with the correct C12 stereochemistry early in the synthesis, the latter features a late-stage introduction of the C12 stereocenter during the ultimate one-pot Michael addition/ketalization
A unified and common intermediate strategy for the asymmetric total synthesis of 3-deoxy-neo-inositol and conduritol E
作者:Amarendra Panda、Rayhan Gafur Biswas、Shantanu Pal
DOI:10.1016/j.tetlet.2016.06.127
日期:2016.8
3-deoxy-neo-inositol and conduritol E starting from d-ribose via a common chiral cyclohexenol derivative. The focal attributes of the synthetic route include stereoselective Grignard reaction, Wittig olefination, ring closing metathesis (RCM), and cisdihydroxylation.
Facile Syntheses of All Possible Diastereomers of Conduritol and Various Derivatives of Inositol Stereoisomers in High Enantiopurity from <i>m</i><i>yo</i>-Inositol
作者:Yong-Uk Kwon、Changgook Lee、Sung-Kee Chung
DOI:10.1021/jo016237a
日期:2002.5.1
Inositol phosphate analogues have been useful in probing the structure-activity relationships between inositol phosphates and biomacromolecules, and in studying biological functions of newly found inositol phosphates. Thus, a systematic and readyaccess to inositol stereoisomers is highly desirable. And practical and convenient syntheses of conduritols and relatedcompounds are also important because of their
Halichondrin B: Synthesis of a C1−C14 Model via Desymmetrization of (+)-Conduritol E
作者:William T. Lambert、Steven D. Burke
DOI:10.1021/ol027389a
日期:2003.2.1
[reaction: see text] A model C1-C14 segment (1) of halichondrin B was synthesized from (+)-conduritol E (7) in 18 steps and 2.9% overall yield. Key features of the synthesis include the novel ozonolytic desymmetrization of C(2)-symmetric diol 6, the early-stage construction of the C-ring which accompanies installation of the crucial C12 stereocenter, and the use of an enol ether C14-ketone surrogate
Desymmetrization of cyclohexadienylsilanes available from Birch reduction of the corresponding arylsilanes is efficiently carried out using Sharpless asymmetric dihydroxylation and aminohydroxylation. Complete diastereocontrol and reasonable enantiocontrol have been attained during the preparation of the desired diols. An excellent regiocontrol has also been observed during aminohydroxylation of dienylsilanol 6b. The resulting diol 8 and hydroxycarbamate 27 have then been elaborated further, offering a straightforward access to various types of cyclitols, aminocyclitols, carbasugars, as well as the antibiotic palitantine 4. The complete functionalization of the original arylsilanes 5 is thus typically achieved in fewer than eight steps with high stereoselectivities and excellent overall yield.