7322-88-5Relevant academic research and scientific papers
Deracemization of (±)-mandelic acid using a lipase-mandelate racemase two-enzyme system
Strauss, Ulrike T.,Faber, Kurt
, p. 4079 - 4081 (1999)
Deracemization of (±)-mandelic acid was achieved by using a novel two- enzyme process consisting of: (i) Pseudomonas sp. lipase catalyzed O- acylation of (±)-mandelic acid in diisopropyl ether; followed by (ii) mandelate racemase catalyzed racemization of the remaining unreacted (R)- mandelic acid in aqueous buffer. When this one-pot sequence was repeated four times, (S)-O-acetylmandelic acid was obtained in 80% isolated yield and >98% ee as the sole product.
The Synthesis of Chiral α-Aryl α-Hydroxy Carboxylic Acids via RuPHOX-Ru Catalyzed Asymmetric Hydrogenation
Guo, Huan,Li, Jing,Liu, Delong,Zhang, Wanbin
, p. 3665 - 3673 (2017/09/11)
A ruthenocenyl phosphino-oxazoline-ruthenium complex (RuPHOX?Ru) catalyzed asymmetric hydrogenation of α-aryl keto acids has been successfully developed, affording the corresponding chiral α-aryl α-hydroxy carboxylic acids in high yields and with up to 97% ee. The reaction could be performed on a gram scale with a relatively low catalyst loading (up to 5000 S/C) and the resulting products can be transformed to several chiral building blocks, biologically active compounds and chiral drugs. (Figure presented.).
METHODS AND COMPOSITIONS FOR PREVENTING OPIOID ABUSE
-
Paragraph 0496; 0497, (2016/11/28)
Abuse-resistant opioid compounds, drug delivery systems, pharmaceutical compositions comprising an opioid covalently bound to a chemical moiety are provided. Methods of delivering an active ingredient to a subject and methods of preventing opioid abuse are also provided.
Penipyridones A-F, Pyridone Alkaloids from Penicillium funiculosum
Zhou, Haibo,Li, Liyuan,Wu, Chongming,Kurtán, Tibor,Mándi, Attila,Liu, Yankai,Gu, Qianqun,Zhu, Tianjiao,Guo, Peng,Li, Dehai
, p. 1783 - 1790 (2016/08/02)
Six new pyridone alkaloids, named penipyridones A-F (1-6), were isolated from the fermentation broth of an Antarctic moss-derived fungus, Penicillium funiculosum GWT2-24. Their structures were elucidated from extensive NMR and MS data. Although they possess the same major chromophore and some of them presented almost mirror ECD spectra, their absolute configurations were found to be uniformly S, as evidenced by X-ray single-crystal diffraction analysis, stereocontrolled total synthesis, and chemical conversions. TDDFT-ECD calculations of compounds 3 and 6 revealed that subtle conformational changes are responsible for the significantly different ECD curves. None of the compounds were cytotoxic (IC50 > 50 μM), while compounds 1, 2, 5, and 7 elicited lipid-lowering activity in HepG2 hepatocytes.
An efficient enzymatic aminolysis for kinetic resolution of aromatic α-hydroxyl acid in non-aqueous media
Chen, Shan,Liu, Fuyan,Zhang, Kuan,Huang, Hansheng,Wang, Huani,Zhou, Jiaying,Zhang, Jing,Gong, Yiwei,Zhang, Dela,Chen, Yiping,Lin, Chang,Wang, Bo
supporting information, p. 5312 - 5314 (2016/11/16)
A new and highly efficient enzymatic aminolysis approach for kinetic resolution of aromatic α-hydroxy acid in non-aqueous media has been developed. The corresponding α-hydroxyl acid ester was employed as the substrate, and commercially available Candida antarctica lipase B is used as the biocatalyst, anhydrous ammonia is the resolving agent. Reactions can be proceeded smoothly in organic solvent at ambient temperatures. High concentration of substrate is allowed due to the application of organic media and the products are obtained in yields of up to 49% with ee values of up to 99%, and with E value of >300, representing an appealing and promising protocol for large-scale preparations.
Synthesis of unsaturated phosphatidylinositol 4-phosphates and the effects of substrate unsaturation on SopB phosphatase activity
Furse, Samuel,Mak, Lokhang,Tate, Edward W.,Templer, Richard H.,Ces, Oscar,Woscholski, Rüdiger,Gaffney, Piers R. J.
supporting information, p. 2001 - 2011 (2015/03/05)
In this paper evidence is presented that the fatty acid component of an inositide substrate affects the kinetic parameters of the lipid phosphatase Salmonella Outer Protein B (SopB). A succinct route was used to prepare the naturally occurring enantiomer of phosphatidylinositol 4-phosphate (PI-4-P) with saturated, as well as singly, triply and quadruply unsaturated, fatty acid esters, in four stages: (1) The enantiomers of 2,3:5,6-O-dicyclohexylidene-myo-inositol were resolved by crystallisation of their di(acetylmandelate) diastereoisomers. (2) The resulting diol was phosphorylated regio-selectively exclusively on the 1-O using the new reagent tri(2-cyanoethyl)phosphite. (3) With the 4-OH still unprotected, the glyceride was coupled using phosphate tri-ester methodology. (4) A final phosphorylation of the 4-O, followed by global deprotection under basic then acidic conditions, provided PI-4-P bearing a range of sn-1-stearoyl, sn-2-stearoyl, -oleoyl, -γ-linolenoyl and arachidonoyl, glycerides. Enzymological studies showed that the introduction of cis-unsaturated bonds has a measurable influence on the activity (relative Vmax) of SopB. Mono-unsaturated PI-4-P exhibited a five-fold higher activity, with a two-fold higher KM, over the saturated substrate, when presented in DOPC vesicles. Poly-unsaturated PI-4-P showed little further change with respect to the singly unsaturated species. This result, coupled with our previous report that saturated PI-4-P has much higher stored curvature elastic stress than PI, supports the hypothesis that the activity of inositide phosphatase SopB has a physical role in vivo. This journal is
3-Aminoquinazolinones as chiral ligands in catalytic enantioselective diethylzinc and phenylacetylene addition to aldehydes
Karabuga, Semistan,Karakaya, Idris,Ulukanli, Sabri
, p. 851 - 855 (2014/06/23)
A series of readily known enantiomerically pure 3-aminoquinazolinones 1a-d were synthesised from easily accessible chiral pool α-hydroxy acids and α-amino acids in only four steps without any requirement of chromatography. These quinazolinones were examined as chiral ligands for catalytic enantioselective diethylzinc and phenylacetylene additions to aldehydes. For enantioselective alkylations, the effects of temperature, solvent, diethylzinc and ligand criteria were analysed, and the desired chiral alcohols were obtained in up to 86% ee. 3-Aminoquinazolinones 1a-d were also shown to be very useful ligands in enantioselective alkynylations of aldehydes. Based upon the optimised conditions, the corresponding propargylic alcohols were obtained in up to 94% ee.
Highly efficient resolution of mandelic acid using lipase from Pseudomonas stutzeri LC2-8 and a molecular modeling approach to rationalize its enantioselectivity
Cao, Yan,Wu, Shanshan,Li, Jiahuang,Wu, Bin,He, Bingfang
, p. 108 - 113 (2014/01/06)
Mandelic acid, a key precursor of chiral synthons, was successfully acylated in diisopropyl ether. The reaction was catalyzed by the lipase from Pseudomonas stutzeri LC2-8, and vinyl acetate was employed as acyl donor. Under the optimized reaction conditions, a resolution of 180 mM (55 g/L) mandelic acid was achieved. (S)-O-Acetyl mandelic acid was enantioselectivity formed in >99% ee at a yield close to the maximum theoretical value for kinetic resolution (50%). The highly substrate tolerable and enantioselective nature of lipase LC2-8 suggests that it is of great potential for the practical resolution of racemic mandelic acid. Additionally, the high enantiopreference of lipase LC2-8 toward (S)-mandelic acid in acetylation was also rationalized through molecular docking and molecular dynamics simulations.
Mandelic acid derived α-aziridinyl alcohols as highly efficient ligands for asymmetric additions of zinc organyls to aldehydes
Rachwalski, Michal,Jarzynski, Szymon,Jasinski, Marcin,Lesniak, Stanislaw
, p. 689 - 693 (2013/07/11)
A straightforward synthesis of a series of new catalysts containing secondary hydroxyl and aziridine moieties as nucleophilic centers built on the chiral scaffold of (S)-(+)-mandelic acid is described. The new compounds have been tested for the enantioselective addition of diethylzinc and phenylethynylzinc to aryl and alkyl aldehydes, which yielded the corresponding chiral alcohols in high chemical yields (up to 95%) and with excellent ee's of ca. 90%. The strong influence of the stereogenic center located at the aziridine subunit on the stereochemical outcome is also reported on.
An organic solvent and thermally stable lipase from Burkholderia ambifaria YCJ01: Purification, characteristics and application for chiral resolution of mandelic acid
Yao, Changjin,Cao, Yan,Wu, Shanshan,Li, Shuang,He, Bingfang
, p. 105 - 110 (2013/01/15)
A solvent-tolerant bacterium Burkholderia ambifaria YCJ01 was newly isolated by DMSO enrichment of the medium. The lipase from the strain YCJ01 was purified to homogeneity with apparent molecular mass of 34 kDa determined by SDS-PAGE. The purified lipase exhibited maximal activity at a temperature of 60 °C and a pH of 7.5. The lipase was very stable below 55 °C for 7 days (remaining 80.3% initial activity) or at 30 °C for 60 days. PMSF significantly inhibited the lipase activity, while EDTA had no effect on the activity. Strikingly, the lipase showed distinct super-stability to the most tested hydrophilic and hydrophobic solvents (25%, v/v) for 60 days, and different optimal pH in contrast with the alkaline lipase from B. cepacia S31. The lipase demonstrated excellent enantioselective transesterification toward the S-isomer of mandelic acid with a theoretical conversion yield of 50%, eep of 99.9% and ees of 99.9%, which made it an exploitable biocatalyst for organic synthesis and pharmaceutical industries.
