Tylosine

Antibiotics approved for use as growth enhancers in Hvestock and poultry include bacitracins, bambermycins, Hncomycin [154-21 -2] penicillin [69-53 ] streptomycin [57-92-1], tetracycHnes, tiamulin [55297-95-5] tylosin [1401-69-0] and virginiamycin [11006-76-1] (61). 

Natural Products. 16-Membered macroHdes are divided into leucomycin- and tylosin-related groups, which differ in the substitution pattern of their aglycones. Multi-factor complexes are usually produced and some compounds have been isolated from culture broths of different organisms and then been given different names. 

Hydrolysis of both neutral sugars from tylosin yields S-O-mycaminosyltylonolide (OMT) (51, R = CHO, R = R" = OH) (238). However, this compound is more conveniendy obtained by hydrolysis of mycarose from the fermentation-derived demycinosyltylosin. Analogous hydrolyses of mycarose from DMOT, GS-77-3, and GS-77-1 yield, respectively, 23-deoxy-5-0-mycaminosyltylonohde (DOMT), 20-deoxo-5-O-mycaminosyltylonohde (GS-77-4), and 5-0-mycaminosyltylactone (GS-77-2), all given in Table 9 (246,250,280). 

The enhanced activity from acylation of the 3- and 4 -hydroxyl groups of leucomycin prompted analogous studies of tylosin. Bioconversion of tylosin by S. thermotokrans yielded 3- and/or 4 -0-acyl derivatives possessing increased activity against certain resistant microorganisms and higher... 

Other macrohdes have been prepared which represent hybrids of stmctures within the 14-membered family, within the 16-membered family, or between the two families. These hybrids have been made by chemical, bioconversion, or genetic manipulations. The 9-0-[(2-methoxyethoxy)methyl]oxime of tylosin (Table 7) was synthesized, using the oxime found in roxithromycin (33) (369). 3-0-Cladinosyl derivatives of 16-membered macrohdes were synthesized in which the neutral sugar of erythromycin (Table 3) was attached to tylosin derivatives at thek 3-hydroxyl group, analogous to its position in erythromycin... 

Tungsten, tricarbonyleyelopentadienylhydrido-reaction with ynamines, 1, 666 Turpin reaction, 3, 1033 Tylophorine occurrence, 4, 478 synthesis, 4, 472, 475 Tylosin... 

The antibiotie Tylosin was produeed in a CSTR using Streptomyees fradiae in a 5 liter laboratory fermenter. For different substrate flow-rates the eoneentrations of produet and biomass were measured [23]. 

Mass balance of biomass ViiC = uC Mass balance of tylosin VqC = uCp... 

Scheme 5. Ketophosphonate-aldehyde condensation in the total synthesis of a tylosin system.

Fig- 5-7 Results (lU/mg) of an interlaboratory study to determinate the potency of tylosin CRS 1 by microbiological assay (diffusion method). 

Cyclic carbonic esters were also prepared, for example, from the cardiac glycoside proscillaridine[257] (where besides CDI the benzyloxycarbonylimidazole was successfully used), ingenol, 2581 the macrolide antibiotic tylosine,[259] and an erythromycin A derivative.12601... 

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