Profadol is a pyrrolidine derivative patented in the 1960s by pharmaceutical company Parke-Davis as opioid analgesic. Profadol acts as a mixed agonist-antagonist of the μ-opioid receptor and in preclinical studies, Profadol precipitates abstinence in morphine-dependent monkeys and can reverse pethidine- induced narcosis in nondependent monkeys. In morphine-dependent human subjects, Profadol was also found to pre¬cipitate acute abstinence syndromes, with a potency 40 to 50 times less than that of nalorphine. Profadol, unlike other morphine-antagonists, does not produce nalorphine-like subjective effects. Over a fourfold range of doses, this drug was found to produce subjective effects indistinguishable from those of morphine. Also unlike other morphine-antagonists, profadol is quite active on the "classical" rodent tests for analgesia. It is about 1.3 times as potent as pethidine on the mouse hot-plate test, and about four times as potent on the rat tail-pressure test.

Fluparoxan (GR50360A) is a potent α2-adrenergic receptor antagonist used in the treatment of central neurodegenerative diseases, depression, the improvement of cognitive dysfunction in schizophrenia and in models of Alzheimer's disease. Fluparoxan was undergoing phase III trials as an antidepressant, but this development was also discontinued because of poor efficacy.

Mocimycin (also known as kyrromycin) was isolated from Streptomyces ramocissimus and tested in vitro against wide range of bacterias. Although having showed good results, drug did not enter clinical trials. Mocimycin acts by binding tightly and specifically to bacterial EF-Tu. Upon administration the antibiotic prevents EF-Tu-GDP from leaving the ribosome and thus inhibits bacterial protein synthesis. Nowadays, the antibiotic is mainly used to study bacterial protein synthesis at the level of elongation factor EF-Tu-GDP release.

Tezacitabine is a cytidine derivative patented by Merrell Dow Pharmaceuticals, Inc. as an antineoplastic and antiviral agent. Tezacitabine acts as irreversible ribonucleotide reductase inhibitor and DNA chain terminator. Tezacitabine shows as potent activity in a broad spectrum of tumor cell lines and in vivo tumor models, including human colon, prostate, and breast tumor xenografts, In clinical trials combination of Tezacitabine and 5-Fluorouracil exerts favor influences in patients with advanced solid tumors particularly in patients with esophageal and other gastrointestinal carcinomas.

Uredepa, a thiotepa derivative, is a antineoplastic, alkylating agent. It has also been used experimentally as an insect chemosterilant.

Suriclone is a dithiinopyrrole derivative patented by Rhone-Poulenc S. A. as a sedative and anxiolytic drug. The mechanism of action by which suriclone produces it's sedative and anxiolytic effects is by modulating GABAA receptors, although suriclone is more subtype-selective than most benzodiazepines. In clinical trials, Suriclone shows a significant anxiolytic effect. The most common adverse reaction was dizziness.

Nosiheptide, an archetypal member of thiopeptide antibiotics, arises from post-translational modifications of a ribosomally synthesized precursor peptide that contains an N-terminal leader peptide (LP) sequence and a C-terminal core peptide (CP) sequence. The precursor peptide of nosiheptide (NosM) is comprised of a leader peptide with 37 amino acids and a core peptide containing 13 amino acids. Nosiheptide exhibits potent activity against multidrug-resistant Gram-positive bacterial pathogens. Nosiheptide exhibited extremely potent activity against all contemporary MRSA strains tested including multiple drug-resistant clinical isolates, with MIC values ≤ 0.25 mg l(-1). Nosiheptide was also highly active against Enterococcus spp. and the contemporary hypervirulent BI/NAP1/027 strain of Clostridium difficile but was inactive against most Gram-negative strains tested. Time-kill analysis revealed nosiheptide to be rapidly bactericidal against MRSA in a concentration- and time-dependent manner, with a nearly 2-log kill noted at 6 h at 10 × MIC. Nosiheptide also demonstrated in vivo activity in a murine model of MRSA infection, and therefore represents a promising antibiotic for the treatment of serious infections caused by contemporary strains of MRSA. Nosiheptide also has significant anti-hepatitis B virus (anti-HBV) activity in cell culture.