Cephalosporanic acid 7-amino

Chemical Name 7-[2-Methoxyimino-2-(2-amino-1,3-thiazol-4-yl)acetamido]-cephalosporanic acid... 

To this solution was added at one time the above-obtained ethyl acetate solution at -15°C, and the resulting mixture was stirred for 1 hour at -10°C to -15°C. The reaction mixture was cooied to -30°C, and water (80 ml) was added thereto. The aqueous layer was separated, adjusted to pH 4.5 with sodium bicarbonate and subjected to column chromatography on Diaion HP-20 resin (Mitsubishi Chemical Industries Ltd.) using 25% aqueous solution of isopropyl alcohol as an eluent. The eluate was lyophilized to give 7-[2-methoxyimino-2-(2-amino-1,3-thiazol-4-yl)acetamido] cephalosporanic acid (syn isomer) (1.8 g), MP 227°C (decomp.). 

Amino-cephalosporanic acid Cyanoacetyl chloride Sodium hydroxide... 

D-Phenylglycine 7-Amino-cephalosporanic acid Isobutyl chloroformate... 

One of the few successful analogues in the p-1act am series with an aliphatic side chain is ceph-ac trile (23). It was made by reacting 7-amino-cephalosporanic acid with cyanoacetyl chloride in the... 

The cephalosporins, discovered in the 1950s, are produced by various species of the mold Cephalosporium. Cephalosporin C (9.46) is the prototype of these antibiotics, and its structure shows a close similarity to the penam stmcture. The 5-thia-l-azabicyclo[4.2.0] octane ring system is therefore called the cepham ring. The parent compound carries the aminoadipate side chain, which can be cleaved to supply the 7-amino-cephalosporanic acid. This amine can easily be acylated and thus forms the basis of many useful derivatives. The 3-acetoxymethyl substiment is also amenable to modifications. 

The specifically 13C-enriched compounds were useful for the signal identification of the 13C NMR spectrum of this microbial product. Spectral comparison of cephalosporin C with a-aminoadipic acid-N-ethylamide, cephalexin, 3-methyl-7 (2-phenoxyacetamido)-3-cepham and 7-amino cephalosporanic acid led to the total signal identification of this antibiotic. The shifts are listed in Table 5.46. 

The term / -lactamase denotes an enzyme which catalyzes the hydrolysis of the amide bond in the /3-lactam ring of 6-amino-penicillanic acid (6-APA) or 7-amino-cephalosporanic acid (7-ACA) and of their A-acyl derivatives (2). Such derivatives are commonly referred to as penicillins [Fig. 1 (I) and cephalosporins Fig. 1 (III), (V), and (VII)], respectively. There is no evidence that any bond other than the amide bond in the intact nucleus of penicillin or cephalosporin is broken by the... 

There are already several examples of chemicals being produced by microbial fermentation of engineered cell factories, whose production through metabolic engineering has been boosted by the use of genomics tools, e.g., 1,3-propanediol used for polymer production, riboflavin used as a vitamin, and 7-aminodeacetoxy-cephalosporanic acid (7-ADCA) used as a precursor for antibiotics production. Furthermore, in the quest to develop a more sustainable society, the chemical industry is currently developing novel processes for many other fuels and chemicals, e.g., butanol, to be used for fuels, organic acids to be used for polymer production, and amino acids to be used as feed. 

To date, the number of penicillin and cephalosporin-based molecules produced by semi- and total synthesis is well in excess of 20000. Most started with modification of the fermentation product, 6-amino-penicillanic acid 20 or the corresponding cephalosporin, 7-amino-cephalosporanic acid 21, both of which can be produced by simple chemical or biochemical deacylation from penicillin or cephalosporin C. The number above is only approximate as a significant proportion of structures from industry were never formally published, or were only mentioned in the patent literature—particularly if they had marginal or no significant activity levels over those which had been reported previously. 

Cephalosporines are derived from natural cephalosporin C produced by Cephalosporinum acre-monium. They possess a cephem nucleus (7-amino-cephalosporanic acid) substituted with two side chains. They are commonly divided into three classes differing in their spectra and toxicity. Cephalosporines can be analyzed both by normal and reversed-phase TLC or HPTLC hence, more efficient separation is obtained on sUanized gel than on bare, untreated silica gel. Mobile phases are polar and similar to those used for penicillins. Acetic add or acetates are very often components of solvents for normal phase (NP) TLC, the ammonium acetate-acetic acid buffer for RP TLC. All cephalosporines can be detected at 254 nm. The detection limit can be diminished by applying reagents such as ninhydrin, iodoplatinate, chloroplatinic acid, or iodine vapor. Alternative to UV detection is bioautography with, for instance. Neisseria catarrhalis. 

Amino-penicillanic acid 4 7-Amino-cephalosporanic acid... 

Amino deacetoxy cephalosporanic acid (7-ADCA) is also produced by the same technology. 

It has been observed critically that the natural products usually exhibit a relatively lower level of antibacterial activity. Therefore, the articulate and judicial cleavage of the amide bond of the aminoadipyl side-chain present in cephalosporin C provides 7-amino-cephalosporanic acid (7-ACA), which is most ideally suitable for the synthesis of a wide range of semisynthetic cephalosporins via acylation of the C(7)-amino fimctional moiety as depicted under ... 

Amino-cephalosporanic acid is converted to its sodium salt and acylated with 1 H-tetrazole-1 -acetyl chloride. The acetoxy group is then displaced by reaction with 5-methyl-1,34-thi-adiazole-2-thiol in buffer solution. The product acid is converted to the sodium salt by NaHCOs. 

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