147-52-4

Unipen,Wyeth,US,1964

Antibacterial.

ChEBI: Nafcillin is a penicillin in which the substituent at position 6 of the penam ring is a (2-ethoxy-1-naphthoyl)amino group. It has a role as an antibacterial drug. It is a penicillin and a penicillin allergen. It is a conjugate acid of a nafcillin(1-).

A stirred suspension of 12.6 grams 6-aminopenicillanic acid in 130 ml dry alcohol-free chloroform was treated with 16 ml triethylamine and then with 13.8 grams of a solution of 2-ethoxy-1-naphthoyl chloride in 95 ml chloroform. After being washed successively with 58 ml each of 1 N and then 0.1 N hydrochloric acid the chloroform solution was extracted with N aqueous sodium bicarbonate (58 ml + 6 ml). The combined bicarbonate extracts were washed with 20 ml ether and then evaporated at low temperature and pressure to give the crude sodium salt of 2-ethoxy-1-naphthylpenicillin [also called sodium 6-(2-ethoxy-1-naphthamido)penicillinate] as a yellow powder (20.3 grams). This was dissolved in 20 ml water at 30°C and diluted with 180 ml n-butanol, also at 30°C, with stirring. Slow cooling to 0°C gave colorless needles of the product.

Nallpen (GlaxoSmithKline).

Antibacterial