Sulfanilamide analogs

Motten, A.G. and Chignell, C.F., 1983, Spectroscopic studies of cutaneous photosensitizing agents. IB. Spin trapping of photolysis products from sulfanilamide analogs, Photochem. Photobiol. 37, 17-26. 

Direct deactivation by a methoxy group makes 3-chloro-6-methoxy-pyridazine unreactive toward sulfanilamide anion in contrast to its 6-chloro, 6-methyl, and 6-hydrogen analogs. Both direct and indirect deactivation of the two chlorines in 3,6-dichloro-4-methoxy-pyridazine (160) are possible the greater reactivity at the... 

Similar success was achieved in the synthesis of analogs of prontosil and sulfanilamide. A number of these analogs were prepared and tested and found to he effective against a variety of infectious diseases. 

Sulfamethoxazole Sulfamethoxazole, ATi-(5-methyl-3-isoxazolyl)sulfanilamide (33.1.20), is synthesized by a completely analogous scheme, except by using 3-amino-5-methylisox-azol as the heterocyclic component [20]. 

Sulfapyridine Sulfapyridine, iV -(2-pyridyl)-sulfanilamide (33.1.21), is also synthesized by an analogous scheme from 4-acetylaminobenzenesulfonyl chloride and 2-amino-pyridine [21-23]. 

Sulfanilamides are antibiotics that serve as structural analogs of para-aminobenzoic acid (PABA), a substrate In the formation of folic acid by many bacteria. Substitution of the sulfanilamide compound In place of PABA In the reaction prevents formation of the critical coenzyme folic acid. 

The sulfonamides are antibacterial agents which are S analogs of p-aminobenzoate. The simplest of these is sulfanilamide. 

Sulfanilamido-6-(p-tolyl8ulfonyl)pyridazine, deactivated by anionization, seems to be about as reactive (150°, 12 hr) toward alkoxide ions as is the 6-chloro analog. In 3-chloro-6-methyl-sulfonylpyridazine the chloro group is preferentially displaced by sulfanilamide anion and by alkylamines and aniline. However, in this substrate as well as in 4-chloro-6-methylsulfonylpyrimidine, the relative reactivity involves their mutual activation as well as their mobilities as leaving groups. 

---