Oxidation of penicillin and dihydrocephalosporin derivatives with ozone

Abstract

and eluted with 200 ml of dry benzene. Evaporation of the solvent gave 0.47 g of product.An analytical sample was obtained by rechromatographing the above material on acid-washed alumina (38.0 g). Elution with 100 ml of dry hexane provided pure 19: ir shows no absorptions above 3000 cm-1; nmr (CCh) 3.69 ppm (s,3, OCH3).

Antibiotic removal from wastewaters: The ozonation of amoxicillin

“…Amoxicillin (AM) molecular structure and its ionizable groups [43]. As reported for the penicillin molecules [28], ozone attack on sulfur atom of amoxicillin could result into the formation of two sulfoxide derivatives (S and R isomers).…”

Oxidation of cefazolin by potassium permanganate: Transformation products and plausible pathways

“…Considering the strong oxidizing ability of Mn(VII), it was highly likely that the fourth O atom was added on one of the formed sulfoxides to transform into sulfone group. As is known, the reduction potential of thioether is closely dependent on electron density of S atom and the electron density is commonly characterized by electrostatic potential charge (Spry, 1972). Generally, the lower the electrostatic potential charge is, the more easily the oxidation of thioether will be.…”

Configuration of phenoxymethyl- and 6-epi phenoxymethylpenicillin sulfoxides

“…The methyl ratio in its integrated nmr spectrum was for 20:2a 2.89:3.00, indicating a deuterium incorporation of 11%. The mass spectrum showed a mixture of 91.5% do, 6.6% di, and 1.9% d2 products.…”

“…Lyophilization of the filtrate gave 194.0 mg (28%) of noncrystalline 6-epi (fi)-sulfoxide 3: mp about 70°dec; [ )20 +116°(c 0.5, acetone); m/e 456; ir (KBr) 3360, 1680, 1515 (amide), 1782 (/3-lactam C=0), 1747, 1212 (ester), 1050 cm 1 (S=0); nmr (CDClg) b 1.34 (s, CHg), 1.46 (s, CH3), 4.52 (s, 3-H), 4.56 (s, OCH2)¡ 4.79 (d, J = 1.5 Hz, 5-H), 5.22 (AB, CH2), 5.54 (dd, J = 1.5, 9 Hz, 6-H), 6.84-7.48 (m, phenyl and amide).…”

“…With ozone as oxidant6•7 in acetone-water (3:2) both phenoxymethyl - (8) and 6-epiphenoxymethylpenicillin benzyl ester (7) afforded a mixture of the corresponding (S)-and (fi)-sulfoxides in a ratio of about 1:1. In the former mixture the two sulfoxides 1 and 9 were isolated by column chromatography, while in the latter mixture 6-epi (S)-sulfoxide 2 was separated from 6-epi (fi)-sulfoxide 3 by fractional crystallization from dry benzene, because the two isomers presented the same R¡ values in our chromatographic systems.…”