79917-54-7

In order to better understand why the formation of sulfilimine intermediates facilitates the oxidation of some aminoazines, we have carried out a computational analysis of 2-aminopyrimidine (II) and S,S-dimethyl-N-(2-pyrimidinyl)sulfilimine (III).We also investigated a system for which the procedure fails: 2-amino-5-nitropyrimidine (VI) and the corresponding sulfilimine (VII).An ab initio SCF approach (GAUSSIAN 82) was used to compute the optimized structures and electrostatic potentials of these molecules.We found that the most negative regions in the sulfilimine intermediates as well as in the original aminoazines are associated with one or both of the ring nitrogens rather than the exocyclic one that is to be oxidized.An important new feature in the case of III is the development of extensive negative potentials above and below the ring plane, which make the exocyclic nitrogen much more accessible to electrophiles than it is in II.Thus the possibility of oxidation occuring at this site is significantly greater in III than in II.The presence of the electron-withdrawing -NO2 in VI prevents the development of extensive, relatively strong negative regions above and below the ring; accordingly there does not occur, in VII, an analogous increase in electrophilic accessibility to the exocyclic nitrogen.

Penicillins and cephalosporins of the formula STR1 wherein A is phenyl, 4-hydroxyphenyl, cyclohexyl, cyclohene-1-yl, cyclohexa-1,4-diene-1-yl, 2-thienyl, 3-thienyl, 2-furyl, 3-furyl or 3,4-disubstituted phenyl, where the substituents, which may be identical to or different from each other, are each chlorine, hydroxyl or methoxy; R1 is an unsubstituted or substituted 5- or 6-membered heterocycle comprising carbon atoms and 1 to 4, preferably 1 to 2, identical or different heteroatoms such as oxygen, sulfur or nitrogen; n is 0 or 1; X is STR2 D is hydrogen, hydroxyl, acetoxy, aminocarbonyloxy, pyridinium, aminocarbonyl-pyridinium or S-Het, where Het is 1-methyl-tetrazol-5-yl, tetrazol-5-yl, 3-methyl-1,2,4-thiadiazol-5-yl, 1,2,4-triadiazol-5-yl, 1,3,4-thiadiazol-5-yl, 2-methyl-1,3,4-thiadiazol-5-yl, 2-methylamino-1,3,4-thiadiazol-5-yl, 2-dimethylamino-1,3,4-thiadiazol-5-yl, 2-formylamino-1,2,4-thiadiazol-5-yl, 2-acetylamino-1,3,4-thiadiazol-5-yl, 2-methyl-1,3,4-oxadiazol-5-yl, 1,2,3-triazol-4-yl or 1,2,4-triazol-3-yl; and E is hydrogen or a protective group which is easily removable in nitro or in vivo, especially an ester-forming group which can be removed under mild conditions by hydrogenation or hydrolysis or other treatments, or an ester-forming group which can easily be split off in the living organism; and, when E is hydrogen, their non-toxic, pharmacologically acceptable salts thereof, such as their alkali metal or alkaline earth metal salts, especially the sodium, potassium, magnesium or calcium salts; their ammonium salts; or their organic amine salts, especially the triethylamine or dicyclohexylamine salts. The compounds are useful as antibiotics.

Compounds of the formula STR1 wherein A is phenyl, 4-hydroxy-phenyl, 2-thienyl or 3,4-dihydroxy-phenyl; and R is STR2 where R1 and R2, which may be identical to or different from each other, are each methylmercapto or amino; Z' is oxygen, sulfur or =NR3 ; R3 is hydrogen, alkyl of 1 to 3 carbon atoms or hydroxy-(alkyl of 1 to 3 carbon atoms); R4 is hydrogen, hydroxyl, hydroxymethyl or methyl; n is 2, 3 or 4; Y is --SO2 NH--, --SO-- or --SO2 --; Z is straight or branched alkylene of 1 to 3 carbon atoms; X is hydroxyl, aminocarbonyl, aminosulfonyl, formylamino, acetylamino, amino, methylsulfinyl, methylsulfonyl or STR3 or --Y--Z--X is STR4 and non-toxic, pharmacologically acceptable salts thereof formed with inorganic or organic bases. The compounds as well as the salts are useful as antibiotics.

2-Aminopyridine, 2-amino-4-methylpyridine, 1-aminoisoquinoline, 2-aminopyrimidine, and 2-aminopyrazine have been converted to the corresponding nitroso compounds by reaction with dimethyl sulfide and N-chlorosuccinimide, deprotonation of the resulting sul

Novel pteridines of formula (I), SPC1 wherein R is a lower alkyl group, optionally substituted with a hydroxy group and R1 and R2 are the same or different and each is a lower alkyl group having together at least 3 carbon atoms or R1 and R2, together with the carbon atom in the pteridine ring structure, form a spirocycloalkyl ring system having 4 to 6 carbon atoms outside the pteridine ring structure, and their method of preparation. The above compounds have bacteriostatic activity.