Lirexapride serotonin 5-HT4 receptor and dopamine D2 receptor agonists. It had been in phase II clinical trials for the treatment of irritable bowel syndrome. However, this research has been discontinued.

Lexacalcitol (KH1060) is over 100 times more active than 1alpha,25-dihydroxyvitamin D3 and is of potential interest in the treatment of psoriasis and other diseases characterized by accelerated cell growth and T lymphocyte activation, which was studied in the clinical trial. KH1060 also prevents type I diabetes in the preclinical investigation without significant effects on calcium or bone metabolism. In addition also was shown that neuroblastoma (NB) cell lines were more susceptible to growth inhibition by KH1060, suggesting its possible use in NB to potentiate the action of retinoids, which are in clinical use for this disease. The underlying biochemical reasons for the increased biological activity of KH1060 are unknown, but it can include 1) metabolic considerations in addition to explanations based upon 2) enhanced stability of KH1060-liganded transcriptional complexes.

Lidanserin is a drug which acts as a combined 5-HT2A and α1-adrenergic receptor antagonist. In conscious spontaneously hypertensive rats intravenous injection of lidanserin caused dose-dependent blood pressure reductions. Lidanserin antagonises the excitatory effect of synaptically released 5-HT on central sympathoexcitatory neurons. Lidanserin is a potential antihypertensive compound which combines vasodilatatory effects due to selective alpha 1-receptor antagonistic action and platelet antiaggregatory, antivasospastic, and vasoprotective properties due to selective 5-HT2-receptor blockade.

Leucocianidol is a vasoprotector. It increases the resistance of vessels and decreases their permeability. Leucocianidol increases the tonicity of the veins. Leucocianidol is used in the management of capillary fragility, hemorrhoids, venolymphatic insufficiency. In combination with lidocaine and hydrocortisone, it is used in the symptomatic treatment of hemorrhoidal crisis. Leucocianidol inhibits 12-lipoxygenase.

Fenmetozole is an alpha-2 adrenergic receptor antagonist which was developed for the treatment of schizophrenic and/or depressed patients, however never reached the market. It was also shown that the drug may reduce symptoms of minimal brain dysfunction in children and antagonize the effect of barbiturates and ethanol.

Lobuprofen is an ester type analgesic, in which the acid moiety (ibuprofen) has peripheral analgesic activity and the alcohol moiety (mCPPol) has central analgesic activity.

Clobenetine is benzomorphan derivative developed by Boehringer-Ingelheim. Clobenetine acts as a sodium channel blocker and displaces radioligand from neurotoxin receptor site 2 of the Na(+) channel in rat brain synaptosomes with IC50 of 49 nM. The IC50 value for the inactivated Na(+) channels was much lower than for Na(+) channels in the resting state. In animal models, clobenetine reduced lesion size in mice and rats when administered 5 min after permanent focal cerebral ischemia at doses that did not impair motor coordination. Clobenetine produced significant analgesic and anti-hyperalgesic effects in the rat model of arthritis, induced by complete Freund's adjuvant. In the early 2000s, the compound was investigated in phase II clinical trial for the treatment of thromboembolic stroke, but no results were reported.

Dalbraminol is a beta-adrenergic blocker, developed by Boehringer Mannheim.

Ibipinabant (IBI) is an orally active potent cannabinoid-1 receptor (CB1R) antagonist. This drug was studied for the treatment of obesity and psychotic disorders. However, the development of the drug was discontinued in November 2008. Now, ibipinabant is only used for laboratory research, especially structure-activity relationship studies into novel CB1 antagonists.

Ciapilome is pyrimidinone derivative patented by German pharmaceutical company Byk Gulden Lomberg Chemical Factory GmbH as xanthine oxidase inhibitor for the treatment of gout, arrhythmia, and heart insufficiencies. Ciapilome causes a pronounced decrease in uric acid blood levels in rats on peroral administration.