75. Derivatives of 6-aminopenicillanic acid. Part IV. Analogues of 2,6-dimethoxyphenylpenicillin in the naphthalene and quinoline series

β-Lactam Antibiotics: Structure-Activity Relationships

“…The 2-alkoxy-1-naphthylpenicillins (nafcillin) can be viewed as analogs of methicillin in which a fused ring contributes the steric effect supplied by one of the o-methoxy groups of methicillin. These penicillins and their corresponding quinoline analogs are stable to penicillinase, whereas the less hindered I-naphthyl, 3-methoxy-2-naphthyl-and 4-quinolinylpenicillins are sensitive to the enzyme (ROSENMAN and WARREN 1962;BRAIN et al 1963).…”

“…Phenyl penicil-lins and equivalent heterocyclic analogs have marked stability to penicillinase when both ortho positions are occupied by any of a large variety of substituents (DOYLE et al 1962 a;BRAIN et al 1963). In fact with a six-membered ring (or a fused ring system of equivalent or greater bulk, e.g., quinacillin) a single ortho substituent of proper type can be sufficient for good penicillinase resistance.…”

Synthesis and characterization of 3-aminoquinoline derivatives and studies of photophysicochemical behaviour and antimicrobial activities

“…Nuclear magnetic resonance spectroscopy ( 1 H and 13 C NMR) 1 H and 13 C NMR spectra for the synthesized (4-alkyl-1-naphthyl)-quinolin-3-ylamide derivatives (6e9) were recorded, and the data obtained are given in the materials and method Fig. 9.…”

“…1 H and l3 C NMR data were obtained using a Bruker Avance 400 MHz spectrometer, with deuterated chloroform (CDCl 3 ) and dimethyl sulfoxide (DMSO-d 6 ) as the solvent. Chemical shifts (d) were given as parts per million (ppm) and coupling constants in units of Hertz (Hz).…”

“…Popular drugs containing naphthalene include the b-blocker drug propranolol used for heart disease, and antimicrobial agents, such as, naftifine and nafcillin, which have antifungal and antibacterial properties, respectively; nafcillin is a penicillin-type antibacterial drug, that has been structurally modified via naphthalene replacement with quinoline, in an effort to overcome drug resistance, specifically by action on the b-lactamase enzyme of Staphylococci [1].…”