PubMed Health⌕ Search

PubMed · 3748508

Perinatal pertussis.

Abstract

Pertussis (whooping cough), a highly contagious disease of childhood, is increasingly recognized among reproductive-age adults and neonates. Described are three cases of maternal-infant pairs in which mother-to-newborn transmission probably occurred and was the cause of extensive morbidity and cost. Means of recognition, treatment, handling, and prevention of this potentially lethal childhood illness are discussed.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

J McGregor, J W Ogle, G Curry-Kane. 1986. Perinatal pertussis.. https://pubmed.ncbi.nlm.nih.gov/3748508/

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related citations

Chemoselective synthesis of erythromycin A ketolides substituted in the C10-methyl group.

The substrate for selective substitution in the C10-methyl group in erythromycin A derivatives was 10,11-anhydro-6O-methyl-descladinosylerythromycin. The latter, as an N-oxide, was reacted with NBS in acetic acid to form an allylic acetate. Nucleophilic substitutions and carbylation by Pd-catalysed cross-coupling reactions provided products substituted in the C10-methyl group. Methods for the preparation of 10-methylene derivatives of 11N,12O-cyclocarbamate 3-ketolides are described. The methylene group is part of an alpha,beta-unsaturated carbonyl system involving the 9-keto group. The products from conjugated addition are substituted in the C10-methyl group.

Erythromycin↗

Determination of the stereochemistry of anhydroerythromycin A, the principal degradation product of the antibiotic erythromycin A.

Anhydroerythromycin A arises from the acid-catalysed degradation of erythromycin A both in vitro and in vivo. It has negligible antibacterial activity, but inhibits drug oxidation in the liver, and is responsible for unwanted drug-drug interactions. Its structure has 18 chiral centres common with erythromycin A, but C-9 (the spiro carbon) is also chiral in anhydroerythromycin and its stereochemistry has not previously been reported; both 9R- and 9S-anhydroerythromycin A are plausible structures. An understanding of the chirality at C-9 was expected to throw light on the mechanism of acid-catalysed degradation of erythromycin A, a subject that has been debated in the literature over several decades. We now report a determination of the three-dimensional structure of anhydroerythromycin A, including the stereochemistry at C-9, by NMR and molecular modelling. In parallel, the relative stereochemistry of anhydroerythromycin A 2'-acetate was determined by X-ray crystallography. Both compounds were shown to have 9R stereochemistry, and anhydroerythromycin A exhibited considerable conformational flexibility in solution.

Erythromycin↗

Preparation of erythromycin analogs having functional groups at C-15.

Chemobiosynthesis has been used to prepare analogs of erythromycins having unique functional groups at the 15-position. Using diketide thioester feeding to genetically engineered Streptomyces coelicolor, analogs of 6-deoxyerythronolide B were prepared having 15-fluoro, 15-chloro, and 15-azido groups. Bioconversion using a genetically engineered mutant of Saccharopolyspora erythraea was used to produce 15-fluoroerythromycin A and 15-azidoerythromycin A. These new erythromycin analogs provide antibacterial macrolides with unique physicochemical properties and functional groups that allow for selective derivatization.

Erythromycin↗