Grignard reactions to chiral oxazolidine aldehydes

Williams, Lorenzo; Zhang, Zhongda; Shao, Feng; Carroll, Patrick J.; Joullié, Madeleine M.

doi:10.1016/0040-4020(96)00672-2

Cited by 118 publications

(63 citation statements)

References 38 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Compounds 16-18 were synthesized by the same procedure with slight modifications. Intermediates 19, 26, and 30 are known compounds (24)(25)(26). Experimental details for 1, 2, 7, 20, 23, 27, and 31 are described.…”

Section: Methodsmentioning

confidence: 99%

See 1 more Smart Citation

Bacterial glycolipids and analogs as antigens for CD1d-restricted NKT cells

Xing

Poles

et al. 2005

Proc. Natl. Acad. Sci. U.S.A.

221

190

View full text Add to dashboard Cite

The CD1 family of proteins binds self and foreign glycolipids for presentation to CD1-restricted T cells. To identify previously uncharacterized active CD1 ligands, especially those of microbial origin, numerous glycolipids were synthesized and tested for their ability to stimulate mouse and human natural killer T (NKT) cells. They included analogs of the well known NKT cell agonist ␣-galactosyl ceramide (␣-GalCer), bacterial glycolipids, and variations of the self-glycolipid, sulfatide. Bacterial glycolipids, ␣-galacturonosyl-ceramides from Sphingomonas wittichii, although structurally similar to ␣-GalCer, have significant differences in the sugar head group as well as the ceramide portion. The Sphingomonas glycosphingolipids (GSLs) and sulfatide variants were shown to activate human NKT cells as measured by IL-4 and IFN-␥ secretion. Moreover, CD1d-dimer staining revealed human NKT cell reactivity toward these GSLs and to the sulfatides in a fashion comparable with ␣-GalCer. Because ␣-GalCer is a marine-sponge-derived ligand, our study here shows that bacterium-derived antigens are also able to stimulate mouse and human NKT cells.

show abstract

Section: Methodsmentioning

confidence: 99%

“…As shown in Fig. 3, compound 19 (3.31 g, 13.5 mmol) (25) was dissolved in 70 ml of dry tetrahydrofuran (THF). The solution was cooled to Ϫ40°C, and vinyl Grignard solution (31 ml of a 1 M solution in THF) was added via a dropping funnel over a period of 1 h. The temperature was kept between Ϫ20°C and Ϫ40°C.…”

Section: Methodsmentioning

confidence: 99%

Bacterial glycolipids and analogs as antigens for CD1d-restricted NKT cells

Xing

Poles

et al. 2005

Proc. Natl. Acad. Sci. U.S.A.

221

190

View full text Add to dashboard Cite

show abstract

“…31 In this context, we have thought of developing a general synthetic approach for the synthesis of all 2-amino-3-alakanols. Herein, we report the synthesis of clavaminols A, C and H from commercially available Garners aldehyde 32,33 in concise and high overall yields. Scheme 1.…”

Section: Resultsmentioning

confidence: 99%

General synthetic strategy for clavaminols A, C and H

Thirupathi¹,

Bharath²,

Mohapatra³

2015

Arkivoc

View full text Add to dashboard Cite

Dedicated to Dr. J. S. Yadav on the occasion of his 65th birthday and in appreciation of his outstanding contributions to synthetic organic chemistry DOI: http://dx.doi.org/10.3998/ark.5550190.p009.281 Abstract A general and efficient synthetic strategy has been developed for the total syntheses of clavaminols A, C and H in 5 to 7 steps starting from (R)-Garners aldehyde following Grignard reaction, Corey-Bakshi-Shibata asymmetric reduction and selective acetylation as key steps with 42 to 59% overall yields, respectively.

show abstract

“…Williams et al reported that the addition of phenylmagnesium bromide to 16 proceeds via the expected non-chelated pathway, but isopropylmagnesium bromide addition follows the chelated pathway. 25 Jurczak et al have shown that lithiated t-butyldimethylsilyl propargyl ether can be added to 16 in either chelated or nonchelated mode furnishing anti-Felkin (syn) or Felkin (anti) products, correspondingly (Scheme 18). 26 High selectivity for antiaddition can be achieved using HMPA (hexamethylphosphoramide) to break the lithium aggregates and chelates.…”

Section: Additions To Garner's Aldehydementioning

confidence: 99%