14347-78-5Relevant academic research and scientific papers
L-(S)-ERYTHRULOSE A NOVEL PRECURSOR TO L-2,3-O-ISOPROPYLIDENE-C3 CHIRONS
Wilde, H. De,Clercq, P. De,Vandewalle, M.,Roeper, H.
, p. 4757 - 4758 (1987)
Starting from L-(S)-erythrulose, now available in larger quantities, the preparation of L-(S)-glyceraldehyde, L-(R)-glycerol and L-(S)-methyl glycerate acetonides, via the protected L-(S)-3,4-O-isopropylideneerythrulose, is described.
Quantitative screening of hydrolase libraries using pH indicators: Identifying active and enantioselective hydrolases
Janes, Lana E.,Loewendahl, A. Christina,Kazlauskas, Romas J.
, p. 2324 - 2331 (1998)
The slowest step in finding a selective hydrolase for synthesis is often the screening step. Researchers must run small test reactions and measure the amounts of stereoisomers formed by HPLC, GC, or NMR. We have developed a colorimetric method to speed up this screening. We quantitatively detect ester hydrolysis using a pH indicator, 4-nitrophenol. We estimate the selectivity by measuring the initial rates of hydrolysis for pure stereoisomers separately. To demonstrate the utility of this method, we screened seventy-two commercial enzymes for enantioselective hydrolysis of racemic solketal butyrate, an important chiral building block. First, we eliminated the twenty hydrolases that did not catalyze hydrolysis of either enantiomer. Next, we measured initial rates of hydrolysis of the pure enantiomers of solketal butyrate. For horse-liver esterase, these initial rates differed by a factor of twelve. Subsequent GC experiments confirmed an enantiomeric ratio of fifteen for this hydrolase. Although this enantioselectivity is moderate, it is the highest enantioselectivity reported for a hydrolysis of solketal esters.
Kinetic resolution of (R,S)-1,2-isopropylidene glycerol (solketal) ester derivatives by lipases
MacHado, Antonio C.O.,Da Silva, Angelo A.T.,Borges, Cristiano P.,Simas, Alessandro B.C.,Freire, Denise M.G.
, p. 42 - 46 (2011)
A study on the enantioselective hydrolysis of (R,S)-1,2-isopropylidene glycerol (4-hydroxymethyl-2,2-dimethyl-1,3-dioxolane, solketal) octanoate catalyzed by different lipases was carried out. Among them, Pseudomonas sp. lipase proved to be the most effective. It was shown that the ester bearing the longer octanoyl acyl chain is a more suitable substrate for this lipase compared to the acetate counterpart. By properly combining enzyme load, temperature and reaction time, either the (S)-alcohol or the remaining ester could be obtained in moderate to high selectivities. Ethyl acetate was found to be the best solvent for the kinetic resolutions effected by such lipase but our results show that toluene may prove useful.
A NEW SYNTHETIC APPROACH TO L-2,3-O-ISOPROPYLIDENE-C3 CHIRONS
Marco, Jose L.,Rodriguez, Benjamin
, p. 1997 - 1998 (1988)
Starting from L-ascorbic acid the preparation of L-(S)-glyceraldehyde and L-(R)-glycerol acetonides, and 1,2-O-isoprpylidene-L-threitol is described.
Synthesis of (R)- and (S)-isopropylidene glycerol
Pallavicini,Valoti,Villa,Piccolo
, p. 5 - 8 (1994)
The preparation of (R)- and (S)-isopropylidene glycerol 1 of high enantiomeric excess (> 98%) was accomplished through salt formation between their hydrogen phthalates with (S)- and (R)-1-methylbenzylamine [MBA] respectively, selective crystallization of these salts and subsequent regeneration of optically active compounds 1 by saponification. The progress of resolution was followed by HPLC analysis on Chiralcel OJ, after converting the hydrogen phthalates into the corresponding mono methyl esters by diazomethane.
Synthesis of Phosphatidylserine and Its Stereoisomers: Their Role in Activation of Blood Coagulation
Mallik, Suman,Prasad, Ramesh,Bhattacharya, Anindita,Sen, Prosenjit
supporting information, p. 434 - 439 (2018/05/23)
Natural phosphatidylserine (PS), which contains two chiral centers, enhances blood coagulation. However, the process by which PS enhanced blood coagulation is not completely understood. An efficient and flexible synthetic route has been developed to synthesize all of the possible stereoisomers of PS. In this study, we examined the role of PS chiral centers in modulating the activity of the tissue factor (TF)-factor VIIa coagulation initiation complex. Full length TF was relipidated with phosphatidylcholine, and the synthesized PS isomers were individually used to estimate the procoagulant activity of the TF-FVIIa complex via a FXa generation assay. The results revealed that the initiation complex activity was stereoselective and had increased sensitivity to the configuration of the PS glycerol backbone due to optimal protein-lipid interactions.
Optically active monoacylglycerols: Synthesis and assessment of purity
Chen, Chao-Yuan,Han, Wei-Bo,Chen, Hui-Jun,Wu, Yikang,Gao, Po
, p. 4311 - 4318 (2013/07/26)
Despite their simple structures, synthesis of 1(or 3)-acyl-sn-glycerols remains a challenge that cannot be ignored because of facile acyl migrations, which not only complicate the synthesis but also make direct GC or HPLC analysis unfeasible. Assessment of the optical purity of monoacylglycerols has, to date, relied almost exclusively on specific rotation data, which are small in value and thus insensitive to impurities. Now, a simple means to "magnify" the small specific rotations has been found, along with practical methods for the measurement of both 1,2-and 1,3-acyl migrations, which offer a convenient and straightforward alternative to Mori's NMR analysis of Mosher esters. With the aid of these methods, a range of conditions for deacetonide removal were examined en route to the synthesis of two natural monoacylglycerols. Refined hydrolysis conditions, along with useful knowledge about the solubility and reactivity of substrates with an ultra long alkyl chain are also presented. Copyright
An esterase with superior activity and enantioselectivity towards 1,2-O-isopropylideneglycerol esters obtained by protein design
Godinho, Luis F.,Reis, Carlos R.,Van Merkerk, Ronald,Poelarends, Gerrit J.,Quax, Wim J.
supporting information, p. 3009 - 3015 (2013/01/15)
The Escherichia coli esterase YbfF displays high activity towards 1,2-O-isopropylideneglycerol (IPG) butyrate and IPG caprylate, and prefers the R-enantiomer of these substrates, producing the S-enantiomer of the IPG product in excess. To improve the pote
Asymmetric synthesis of (4S,5S)-2-oxo-4-phenyloxazolidine-5-carboxylic acid using a 1,2-addition of PhMgBr to an N-sulfinimine derived from (R)-glyceraldehyde acetonide and (S)-t-BSA
Babu, K. Chandra,Vysabhattar, Raman,Srinivas,Nigam, Satish,Madhusudhan,Mukkanti
experimental part, p. 2619 - 2624 (2011/01/05)
We report an asymmetric synthesis of (4S,5S)-2-oxo-4-phenyloxazolidine-5- carboxylic acid via stereoselective addition of phenylmagnesium bromide (PhMgBr) to an N-sulfinimine derived from (R)-glyceraldehyde acetonide. (S)- and (R)-Glyceraldehyde acetonides, important chiral synthons in synthetic organic chemistry, are prepared from the corresponding epichlorohydrin using an identical synthetic methodology.
A genetic selection system for evolving enantioselectivity of enzymes
Reetz, Manfred T.,Hoebenreich, Horst,Soni, Pankaj,Fernandez, Layla
scheme or table, p. 5502 - 5504 (2009/04/13)
As an alternative to screening in the directed evolution of enantioselective enzymes, a selection system has been implemented for a lipase-catalyzed hydrolytic kinetic resolution of a chiral ester. The Royal Society of Chemistry.
