Azamulin [14-O-(5-(2-amino-1,3,4-triazolyl)thioacetyl)-dihydromutilin] is an azole derivative of the pleuromutilin class of antiinfectives. Azamulin is a selective, irreversible inhibitor of cytochrome P450 (CYP) 3A isoforms (IC50 values range from 26 to 240 nM for CYP3A4 and CYP3A4/5 from different sources). It is at least 50-fold less potent against CYP2J2 and 100-fold less effective against all other CYP isoforms. Azamulin potently blocks the hydroxylation of testosterone and midazolam by CYP3A4. Azamulin exhibited remarkable antibacterial activity against all Gram-positive pathogens including MRSA, PRSP, and VRE, except for E. faecalis.

Metesculetol (permethol) is a vitamin P derivative. It increases capillary resistance and reduces membrane permeability. Permethol is for damaged gums and helps to stop gum bleeding, relieves inflammation and nourishes the gum tissues. It is used as a component of products for oral cavity care.

Tetriprofen is a hydratropic acid derivative patented by Swiss chemical company CIBA Ltd as an antinociceptive and anti-inflammatory 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.

Fosmenic acid was used for the treatment of atherosclerosis. Information about the current use of this drug is not available.

Fosmidomycin (3-(formylhydroxyamino)-propylphosphonic acid mono-sodium salt, 3-(N-formyl-N-hydroxyamino)-propylphosphonic acid mono-sodium salt, FR-31564) is a potent inhibitor of P. falciparum 1-deoxy-D-xylulose-5-phosphate reductoisomerase (PfDXR), developed by Albert Schweitzer Hospital for P. falciparum malaria treatment. Fosmidomycin was originally isolated as natural antibiotic from Streptomyces lavendulae. Fosmidomycin is active against a broad range of enterobacteria, but not against Gram-positive organisms or anaerobes. Fosmidomycin was developed as far as an early phase II study for the treatment of urinary tract infections by Fujisawa Pharmaceutical Company (Osaka, Japan) in the early eighties, but these trials have been discontinued. In recent clinical studies, it was shown that fosmidomycin is effective in curing uncomplicated Plasmodium falciparum malaria in humans. The treatment was well tolerated and resulted in a fast parasite and fever clearance. However, the high rate of recrudescence precludes the use of fosmidomycin as a monotherapy. In drug combination studies, the synergy of fosmidomycin with clindamycin was observed. Clinical studies with a fosmidomycin-clindamycin combination are currently ongoing.

Tigloidine is a tropane alkaloid and a naturally occurring analog of atropine, found in small quantities in Duboisia myoporoides. Tigloidine has been found to be beneficial in the treatment of Parkinsonism, Huntington’s Chorea and spastic paraplegia. Tigloidine may provide relief in parkinsonian patients by increasing the gamma-efferent activity and reducing alpha motoneurone activity. In preclinical models, Tigloidine failed to reverse sedation and ptosis in rats induced by reserpine and tetrabenazine. In mice, amphetamine response was not significantly affected by Tigloidine or atropine. However, in the cat and dog, it was markedly facilitated by Tigloidine but not by atropine.

Tiapirinol is a thiazine derivative patented by Tanabe Seiyaku Co., Ltd. as a low toxic compound useful to prevent hypohepatia. In acute toxicity tests on mice, the toxicity of Tiapirinol is lower than that of pyridoxal phosphate and other vitamin B6 derivative. Tiapirinol showed vitamin B6 activity approximately equivalent to that of pyridoxal phosphate or pyridoxine for the growth of vitamin B6 deficient rats and also for the convulsions caused by antivitamin B6 agents.