26395-99-3Relevant articles and documents
On the substrate preference of glutaryl acylases
Rosini, Elena,Monelli, Claudia Stella,Pollegioni, Loredano,Riva, Sergio,Monti, Daniela
experimental part, p. 52 - 58 (2012/04/11)
The substrate preferences of three acylases - two wild-type enzymes and an evolved variant obtained by directed evolution - which are prototypical enzymes for glutaryl-7-ACA acylase and cephalosporin C acylase subfamilies, have been investigated. A preliminary screening of enzymes' performances on a large set of substrates has been carried out by a colorimetric assay performed in 96-well plates and by a pH-Stat monitoring the hydrolytic activities. Subsequently, kinetic data for selected substrates have been determined, thus elucidating the substrate preference of members of glutaryl-7-ACA acylase vs. cephalosporin C acylase subfamilies. These achievements pave the way to the ability of choosing the best enzyme for the hydrolysis of different compounds of industrial importance.
PROCESS FOR THE PRODUCTION OF CEPHALOSPORINS
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Page/Page column 10-11, (2012/03/27)
The present invention relates to a composition comprising ≥85 wt% of an N-deacylated cephalosporin, a process for making the same and the use of said N-deacylated cephalosporin in the preparation of highly pure semi synthetic cephalosporins.
The multilayer polymer film
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, (2007/10/09)
The use of multilayer film structure comprising at least two unfilled layers of polymeric material substantially devoid of opacifying agent and at least two filled layers of polymeric material wherein said filled layers comprise at least 5% by weight of o
Amino ester hydrolase from Xanthomonas campestris pv. campestris, ATCC 33913 for enzymatic synthesis of ampicillin
Blum, Janna K.,Bommarius, Andreas S.
scheme or table, p. 21 - 28 (2010/12/19)
α-Amino ester hydrolases (AEH) are a small class of proteins, which are highly specific for hydrolysis or synthesis of α-amino containing amides and esters including β-lactam antibiotics such as ampicillin, amoxicillin, and cephalexin. A BLAST search revealed the sequence of a putative glutaryl 7-aminocephalosporanic acid (GL-7-ACA) acylase 93% identical to a known AEH from Xanthomonas citri. The gene, termed gaa, was cloned from the genomic DNA of Xanthomonas campestris pv. campestris sp. strain ATCC 33913 and the corresponding protein was expressed into Escherichia coli. The purified protein was able to perform both hydrolysis and synthesis of a variety of α-amino β-lactam antibiotics including (R)-ampicillin and cephalexin, with optimal ampicillin hydrolytic activity at 25 °C and pH 6.8, with kinetic parameters of kcat of 72.5 s-1 and KM of 1.1 mM. The synthesis parameters α, βo, and γ for ampicillin, determined here first for this class of proteins, are α = 0.25, βo = 42.8 M-1, and γ = 0.23, and demonstrate the excellent synthetic potential of these enzymes. An extensive study of site-directed mutations around the binding pocket of X. campestris pv. campestris AEH strongly suggests that mutation of almost any first-shell amino acid residues around the active site leads to inactive enzyme, including Y82, Y175, D207, D208, W209, Y222, and E309, in addition to those residues forming the catalytic triad, S174, H340, and D307.
Glutaryl Acylases: One-Reaction Enzymes or Versatile Enantioselective Biocatalysts?
Raimondi, Stefano,Monti, Daniela,Pagnoni, Ugo Maria,Riva, Sergio
, p. 783 - 789 (2007/10/03)
A significant broad substrate specificity, that crosses over the usual β-lactam derivatives, has been observed with an industrial glutaryl-7-aminocephalosporanic acid acylase (GA). This enzyme possesses significant enantioselective amidase and even esterase activity, with a stereopreference for the S-enantiomer. The easy separation of products from unreacted reagents, possessing different physical-chemical properties, is achieved by solvent extraction, avoiding chromatography or distillation during reaction work-up.
Enzymatic hydrolysis of β-lactam antibiotics at low pH in a two-phase "aqueous solution - Water-immiscible organic solvent" system
Chilov, Ghermes G.,Svedas, Vytas K.
, p. 699 - 707 (2007/10/03)
The application of the two-phase "aqueous solution - water-immiscible organic solvent" system is suggested not for effective biocatalytic synthesis, but for hydrolytic purposes. Enzymatic hydrolysis of benzylpenicillin and N-phenylacetamidodesacetoxycepha
A facile synthesis of 7-amino-3-desacetoxycephalosporanic acid derivatives by indium-mediated reduction of 3-iodomethylcephems in aqueous media
Chae, Hyungsun,Cho, Sangwon,Keum, Gyochang,Kang, Soon Bang,Pae, Ae Nim,Kim, Youseung
, p. 3899 - 3901 (2007/10/03)
An efficient reductive conversion of 3-iodomethylcephalosporin and 3- acetoxymethylcephalosporin derivatives mediated by indium into the corresponding 3-methylcephems and 3-methylenecephams in moderate to good yields has been developed in an aqueous system. 3-Methylenecephams are converted into the corresponding 3-methylcephems under previously reported basic conditions quantitatively. (C) 2000 Elsevier Science Ltd.
Process for P-nitrobenzyl ester cleavage in cephalosporin
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, (2008/06/13)
A process for converting cephalosporin p-nitrobenzyl ester (Formula I) to the corresponding cephalosporin free acid (Formula II) comprising treating the cephalosporin p-nitrobenzyl ester with a metal selected from the group consisting of iron, magnesium, aluminum, and tin, and with hydrochloric acid in a mixture of water and a water-miscible organic solvent. Preferably, the metal is iron in the form of a fine powder, and the reaction is carried out at a temperature in the range of 30°-50° C.
Selective deprotective method using palladium-water soluble catalysts
Lemaire-Audoire,Lemaire-Audoire, Sandrine,Savignac,Savignac, Monique,Blart,Blart, Errol,Pourcelot,Pourcelot, Guy,Genet,Genet, Jean Pierre,Bernard,Bernard, Jean-Marie
, p. 8783 - 8786 (2007/10/02)
Allylcarboxy and Allyloxycarbonyl groups can be removed without affecting dimethylallylcarboxy and cinnamylcarboxy groups in the same molecule. using Pd(O) water soluble catalyst prepared in situ, with diethylamine as allyl scavenger. Homogeneous or biphasic media are suitable: the yields of deprotection are quantitative.
Synthesis of potential impurities of cefalexin and cefradine
Hendrix,Roets,Bervoets,Thomas,Pijcke,Busson,Janssen,Hoogmartens
, p. 215 - 219 (2007/10/02)
The synthesis of some impurities of the cephalosporin antibiotics cefalexin and cefradine is described. These impurities which may be present in commercial samples are formed during the semi-synthetic preparation of these antibiotics or upon their degradation. The preparation of these compounds enables the validation of selective quantitative analytical methods, such as column liquid chromatography and thin layer chromatography.
