Lincomycins

Lincomycins

Properties and uses: The antibiotic lincomycin is obtained from Actinomycetes, Streptomyces, and Lincolnensis. The ability of lincomycin to penetrate into bones, adds to its qualities and it gets promoted in the chemotherapy of bone and joint infections by penicillin resistant strains of S. aureus. Variation of the substituents on pyrrolidine portion and C-5 side chain affects the activity. Some of the examples are as follows:

i.N-demethylation imparts activity against gram-negative bacteria.

ii. Increase in the chain length of the propyl substitutent at C-4 position in pyrrolidine moiety up to n-hexyl increase in vivo activity.

iii. The thiomethyl ether of α-thiolincosamide moiety is essential for activity.

iv. Structural modifications at C-7 position, such as introduction of 7S chloro or 7R-OCH3, change the physiochemical parameters of the drug (i.e. partition coefficient), and thus, alter the activity spectrum and pharmacokinetic properties. The usual side effects include skin rashes, nausea, vomiting, and diarrhoea.

Dosage forms: Lincomycin HCl capsules I.P.