Rosoxacin (also known as acrosoxacin, tradename Eradacil) is a

quinolone antibiotic A quinolone antibiotic is a member of a large group of broad-spectrum bacteriocidals that share a bicyclic core structure related to the substance 4-quinolone. They are used in human and veterinary medicine to treat bacterial infections, as we ...

indicated for the treatment of urinary tract infections and certain sexually transmitted diseases. Rosoxacin is not available in the United States. It was developed in 1978 by George Lesher and his colleagues at Winthrop-Stearns (now part of sanofi-aventis), as an extension of the work that originally led to nalidixic acid. It is classified as a first generation quinolone.

Synthesis

The synthesis of rosoxacin begins with a modified

Hantzsch pyridine synthesis The Hantzsch pyridine synthesis or Hantzsch dihydropyridine synthesis is a multi-component organic reaction between an aldehyde such as formaldehyde, 2 equivalents of a β-keto ester such as ethyl acetoacetate and a nitrogen donor such as ammoni ...

employing as component parts ammonium acetate, two equivalents of

methyl propiolate Methyl propiolate is an organic compound with the formula HC2CO2CH3. It is the methyl ester of propiolic acid, the simplest acetylenic carboxylic acid. It is a colorless liquid that is miscible with organic solvents. The compound is a reagent a ...

, and one of 3-nitrobenzaldehyde. Oxidation of the resulting dihydropyridine (2) with nitric acid followed by saponification, decarboxylation, and reduction of the nitro group with iron and HCl acid gives aniline 3. This undergoes the classic sequence of Gould-Jacobs reaction with methoxymethylenemalonate ester to form the 4-hydroxyquinoline ring, and then alkylation with ethyl iodide and saponification of the ester to complete the synthesis of the antibacterial agent rosoxacin (4).

References

Quinolone antibiotics 4-Pyridyl compounds Carboxylic acids {{antibiotic-stub

Synthesis

See also

References