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N Castagnoli

Publications and source records attributed to N Castagnoli.

At least 163 records · Page 9Linked to original sources
PubMed1970

Biosynthesis of N-(alpha-hydroxyethyl) lysergamide, a metabolite of Claviceps paspali Stevens and Hall.

1. The biosynthetic origin of the amide substituent of N-(alpha-hydroxyethyl)lysergamide has been studied. 2. [1-(14)C]Acetate, [(14)C]formate, [2-(14)C]mevalonic acid lactone, [2-(14)C]indole, dl-[3-(14)C]tryptophan, dl-[3-(14)C]serine, dl-[2-(14)C]alanine and [2-(14)C]pyruvate were efficiently incorporated into the alkaloid, but not dl-[1-(14)C]alanine or [1-(14)C]pyruvate. 3. Only the dl-[2-(14)C]alanine- and [2-(14)C]pyruvate-derived alkaloid contained appreciable radioactivity in the amide substituent. 4. l-[(15)N]Alanine-derived alkaloid was shown to be specifically labelled in the amide nitrogen. However, l-[(14)C,(15)N]alanine was found to be incorporated into the methylcarbinolamide substituent with an appreciable increase in the (15)N/(14)C ratio, suggesting that alanine is not the direct precursor of this moiety.

Acetates↗
PubMedDate not supplied

The metabolism of tertiary amines.

The metabolism of tertiary amines is mediated primarily by cytochrome P-450 and MFAO, leading to alpha-C oxidation and N-oxidation, respectively. We have discussed how lipophilicity, basicity, steric hindrance, and stereochemistry can effect the outcome of metabolism as well as species, sex, and age. The proposed oxidation of tertiary amines to iminium ions by cytochrome P-450 may explain the isolation of various intramolecular and cyanide-trapped metabolites. N-oxides may represent a smaller percentage of the overall in vitro metabolism of tertiary amines due to the postmortem inactivation of MFAO. In addition N-oxide reducing enzymes present in vivo and in vitro may influence the extent of N-oxide formation. In general, definite conclusions about substrate requirements have been difficult to formulate because of the numerous biological and physical parameters affecting the outcome of metabolism. More singularly directed research on a single species of animal and a wide variety of substrates or vice versa would greatly increase our understanding of the potential metabolism of tertiary amine xenobiotics.

Amines↗