Penicillin aldehydes

After oral administration to the dog, penamecillin (VII), which is the acetoxymethyl ester of benzylpencillin, produces prolonged benzylpencillin serum levels.According to pharmacokinetic evidence O, the penamecillin is slowly absorbed unchanged throughout the intestinal tract and then is rapidly hydrolyzed to benzylpenicillin by nonspecific esterases. Compound VIII is an example of the hitherto unknown penicillin aldehydes for which a general synthesis was developed. 

Aziridinium ion-based click chemistry provides convenient access to pyrazolo[l,2-ajpyrazoles, active inhibitors of penicillin-binding proteins [58, 59]. Ring-opening of aziridinium ions 32 at the benzylic position with hydrazine, followed by intramolecular cyclization, gave pyrazolidin-3-ones 37 in excellent yields (Scheme 12.27). Heating of the hydrazides 37 with aromatic aldehydes at reflux in absolute... 

Fig.1 Schematic illustration of the immobilization of penicillin G acylase on glutamate-pillared LDHs. Reaction of the primary amino groups of the intercalated glutamate ions with glutaraldehyde through Schiff s base formation is followed by covalent coupling of the residual aldehyde groups with the free amino groups of the enzyme...

Was this your answer Acetaldehyde aldehyde penicillin G amide (two amide groups), carboxylic acid testosterone alconol and ketone morphine alcohol, phenol, ether, and amine. 

Pivaloyloxymethyl (Pom) esters are useful as prodrugs of penicillin and other 0-lactam antibiotics owing to their easy hydrolysis in vivo by ubiquitous non-specific esterases. Mascaretti and co-workers showed that Pom esters can also by cleaved under mild conditions with 2 equivalents of bis(tri-/i-butyltin)oxide as shown in Scheme 6.32. The intermediate tributylstannyl esters are readily hydrolysed on treatment with water to release the carboxylic acid. Functional groups such as aldehydes, thioacetals, amides, vinyl bromides, and nitro compounds are compatible.22... 

The halogen-magnesium exchange of a-halo carbonyl compounds has been reported to afford magnesium enolates which react with aldehydes to yield aldol products [107, 108]. The application of this reaction to the synthesis of penicillin derivatives has been reported (Scheme 3.94) [109-111]. 

The structure of the penicillins (3.1) was established in the days before spectroscopic methods were routinely applied to structure determination. The degradative evidence for the structure of the penicillins is best understood if it is realized that the central carbon (C-5) of the thiazolidine ring in the core of the structure is a masked aldehyde and, secondly, that the p-lactam is a strained four-membered ring in which the lactam does not behave as a typical amide. The shape of the ring precludes the normal amide resonance and hence hydrolysis of the lactam takes place more easily than would be expected for an amide. This hydrolysis then places a carboxylic acid in the p-position to the masked aldehyde so that decarboxylation of a p-keto acid can occur. 

Aldehyde synthesis [1, 730, before references]. Gottstein et a/.48 developed an efficient method for the transformation of a tertiary amine salt of a penicillin (1) according to Scheme I into the thioacid salt (2) through the ethoxy formic anhydride. The salt is then desulfurized with No. 28 Raney nickel catalyst (W. R. Grace Co.)... 

The penicillin nucleus has been utilized for the construction of the dihy-drothiazine ring.65 Thus when treated with chromium(II) chloride, the penam 85 was converted into compound 87 clearly, the amino aldehyde 86 is implicated in the reaction. 

The penicillins are hydrolysed by hot dilute inorganic acids one carbon atom is eliminated as carbon dioxide (CO2) and two products are obtained in equimolecular proportions, one being an amine, Pencillamine and the other an aldehyde, Penniloaldehyde. 

All the penicillins give the same amine, but different aldehydes, because it bears the variable component R in it. 

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