13894-63-8Relevant articles and documents
Mechanochemical enzymatic resolution of N-benzylated-β3-amino esters
Pérez-Venegas, Mario,Reyes-Rangel, Gloria,Neri, Adrián,Escalante, Jaime,Juaristi, Eusebio
supporting information, p. 1728 - 1734 (2017/09/27)
The use of mechanochemistry to carry out enantioselective reactions has been explored in the last ten years with excellent results. Several chiral organocatalysts and even enzymes have proved to be resistant to milling conditions, which allows for rather efficient enantioselective transformations under ball-milling conditions. The present article reports the first example of a liquid-assisted grinding (LAG) mechanochemical enzymatic resolution of racemic β3-amino esters employing Candida antarctica lipase B (CALB) to afford highly valuable enantioenriched N-benzylated-β3-amino acids in good yields. Furthermore the present protocol is readily scalable.
Proton pump inhibitors
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Paragraph 0261, (2015/11/16)
A proton pump inhibitor containing a compound represented by the formula (I) wherein X and Y are the same or different and each is a bond or a spacer having 1 to 20 carbon atoms in the main chain, R 1 is an optionally substituted hydrocarbon group or an optionally substituted heterocyclic group, R 2 , R 3 and R 4 are the same or different and each is a hydrogen atom, an optionally substituted hydrocarbon group, an optionally substituted thienyl group, an optionally substituted benzo[b]thienyl group, an optionally substituted furyl group, an optionally substituted pyridyl group, an optionally substituted pyrazolyl group, an optionally substituted pyrimidinyl group, an acyl group, a halogen atom, a cyano group or a nitro group, R 5 and R 6 are the same or different and each is a hydrogen atom or an optionally substituted hydrocarbon group, which has a superior proton pump action and shows an antiulcer activity and the like after conversion to a proton pump inhibitor in the body, or a salt thereof. or a prodrug thereof is provided.
Characterization of FabG and FabI of the Streptomyces coelicolor dissociated fatty acid synthase
Singh, Renu,Reynolds, Kevin A.
, p. 631 - 640 (2015/03/31)
Streptomyces coelicolor produces fatty acids for both primary metabolism and for biosynthesis of the secondary metabolite undecylprodiginine. The first and last reductive steps during the chain elongation cycle of fatty acid biosynthesis are catalyzed by FabG and FabI. The S. coelicolor genome sequence has one fabI gene (SCO1814) and three likely fabG genes (SCO1815, SCO1345, and SCO1846). We report the expression, purification, and characterization of the corresponding gene products. Kinetic analyses revealed that all three FabGs and FabI are capable of utilizing both straight and branched-chain β-ketoacyl-NAC and enoyl-NAC substrates, respectively. Furthermore, only SCO1345 differentiates between ACPs from both biosynthetic pathways. The data presented provide the first experimental evidence that SCO1815, SCO1346, and SCO1814 have the catalytic capability to process intermediates in both fatty acid and undecylprodiginine biosynthesis.
Polystyryl-BEMP as an efficient recyclable catalyst for the nucleophilic addition of nitroalkanes to α,β-unsaturated carbonyl compounds under solvent-free conditions
Ballini,Barboni,Castrica,Fringuelli,Lanari,Pizzo,Vaccarob
experimental part, p. 1218 - 1224 (2009/05/30)
2-tert-Butylimino-2-diethylamino-1,3-dimethylperhydro-1,3, 2-diazaphosphorine supported on polystyrene (PS-BEMP) is an efficient catalyst for the addition of nitroalkanes (1-1.5 equiv.) to α,β-unsaturated carbonyl compounds (1.0 equiv.) in the absence of a reaction medium (solvent-free conditions). The corresponding γ-nitro carbonyl compounds have been isolated in excellent yields but the catalyst can be satisfactorily recovered and used for only 3 times due to the magnetic stirring which caused crunching of the catalyst beads thus hampering its complete recovery. To optimize the catalyst's reuse and improve the environmental efficacy of solvent-free conditions, the first solvent-free cyclic continuous-flow reactor has been set up. This reactor has allowed the product to be isolated in an almost quantitative yield by using a very small amount of organic solvent, making the recovery and reuse of the catalyst efficient and reproducible.
PROTON PUMP INHIBITORS
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, (2008/06/13)
A proton pump inhibitor containing a compound represented by the formula (I) wherein X and Y are the same or different and each is a bond or a spacer having 1 to 20 carbon atoms in the main chain, R1 is an optionally substituted hydrocarbon group or an optionally substituted heterocyclic group, R2, R3 and R4 are the same or different and each is a hydrogen atom, an optionally substituted hydrocarbon group, an optionally substituted thienyl group, an optionally substituted benzo[b]thienyl group, an optionally substituted furyl group, an optionally substituted pyridyl group, an optionally substituted pyrazolyl group, an optionally substituted pyrimidinyl group, an acyl group, a halogen atom, a cyano group or a nitro group, R5 and R6 are the same or different and each is a hydrogen atom or an optionally substituted hydrocarbon group, which has a superior proton pump action and shows an antiulcer activity and the like after conversion to a proton pump inhibitor in the body, or a salt thereof. or a prodrug thereof is provided.
A convenient one-pot PCC oxidation-Wittig reaction of alcohols
Bressette, Andrew R.,Glover IV, Louis C.
, p. 738 - 740 (2007/10/03)
A simple one-pot process for the PCC oxidation of alcohols followed by in situ trapping of the aldehyde with a Wittig reagent is described.
Mild esterification and transesterification of carboxylic acids catalyzed by tetracyanoethylene and dicyanoketene dimethyl acetal
Masaki, Yukio,Tanaka, Nobuyuki,Miura, Tsuyoshi
, p. 55 - 56 (2007/10/03)
A π-acid tetracyanoethylene (TCNE) and its derivative dicyanoketene dimethyl acetal (DCKDMA) were found to catalyze esterification of lauric acid with various types of alcohols. This method was successfully applied to methyl esterification of a variety of carboxylic acids including aromatic, α,β-unsaturated, α-hydroxy, and N-Cbz and N-Boc-protected α-amino acids without racemization at the range from room temperature to 60 °C. TCNE was also found to operate as a catalyst in transeslerification reaction of methyl laurate.
Wittig reactions in the presence of silica gel
Patil, Vijay J.,Maevers, Ursula
, p. 1281 - 1284 (2007/10/03)
Wittig reactions, of stable phosphorous ylids, when carried out in presence of silica gel, in hexane, provide a fast, efficient and simple method to obtain α:β unsaturated compounds in high yields and high purity.
Ruthenium-catalyzed oxidations for selective syntheses of ketones and acyl cyanides. Selective acylation of amino compounds with acyl cyanides
Murahashi,Naota
, p. 433 - 440 (2007/10/02)
Oxidation of alcohols to the corresponding carbonyl compounds with tert-butyl hydroperoxide in the presence of dichlorotris(triphenylphosphine)ruthenium catalyst gives the corresponding carbonyl compounds with high efficiency. This method can be applied to the oxidation of cyanohydrins to give acyl cyanides which are versatile synthetic intermediates. Acylation of amino compounds with acyl cyanides thus obtained proceeds chemoselectively. Thus, the reaction of amino alcohols with acyl cynides gives N-acylated products exclusively. In the similar N-acylation of polyamines primary amines are selectively acylated in the presence of secondary amines. These reactions are highly useful for the synthesis of spermidine and spermine alkaloids such as spermidine alkaloids such as spermidine siderophores. Dimeric cyclocoupling reaction of diacyl cyanides such as iso- and terephthaloyl cyanides with polyamines can be performed under the similar reaction conditions to give the corresponding polyazamacrocycles with high efficiency.