Benethamine penicillin is a medium-long-acting insoluble penicillin salt. After a single injection, this salt acts and bacteriostatic level of penicillin is maintained in the blood for three to six days.

Phenyracillin is the 2,5-diphenylpiperazine salt of benzylpenicillin. It is antibiotic from Pencillium spp. and also other fungal spp. Shows activity against gram-positive bacteria. Phenyracillin was well tolerated.

FIBRACILLIN is a semisynthetic antibacterial agent.

Fomidacillin (also known as BRL 36650) is a type of penicillin with antibacterial activity. Studies on volunteers have shown that the drug possessed the bactericidal activity and could be a candidate for the treatment of gram-negative bacillary infections. However, information about the further development of this drug is not available.

Furbucillin is a synthetic antibacterial agent that has never been marketed. Information about the current use of this drug is not available.

Prazocillin is 6-aminopenicillanic acid derivative patented by Chinoin Gyogyszer es Vegyeszeti Termekek Gyara Rt. as a bactericidal compound. The activity of Prazocillin against Staphylococcus aureus strains was the same as that of dikloxacillin, but Prazocillin was more active against Bacillus subtilis ATCC 6633. Prazocillin had a bactericidal effect on a penicillin-resistant S. aureus strain at concentrations of 1 μg/ml. Pyrazocillin inhibits bacterial penicillinase in vitro.

Thiphencillin is a penicillin analog patented by Abbott Laboratories as an antibacterial agent. Thiphencillin shows potent antibacterial activity against various species and genera of pathogenic bacteria.

Benzylpenilloic acid is a metabolite of benzylpenicillin. It is produced by hydrolysis of when beta-lactam ring of benzylpenicillin. Along with some other metabolites of penicillin, benzylpenilloic acid is responsible for the allergic reaction to beta-lactam antibiotic. It is a component of a minor determinant mixture (MDM) reagent which is used to evaluate sensitivity to penicillin in the clinic.

APD668 is a novel, highly potent and orally active glucose-dependent insulinotropic receptor (GDIR) agonist intended to more efficiently stimulate insulin release by beta cells in response to elevated blood glucose levels, and to avoid hypoglycemia. Ortho-McNeil's initial clinical studies evaluated healthy volunteers and patients with type 2 diabetes in randomized, double-blind, placebo-controlled trials evaluating the safety, tolerability, pharmacokinetics and pharmacodynamics of single and multiple (14 day) escalating doses of APD668. Based on the data from those studies, Ortho-McNeil has decided to put APD668 on hold and has advanced a potentially more potent Arena discovered GDIR agonist into preclinical development.