Identification of tetracyclic lactams as NMDA receptor antagonists with potential application in neurological disorders

Pharmacokinetics, absolute bioavailability, and tissue distribution of WJ-14, a novel N-methyl-d-aspartate receptor antagonist, in rats by liquid chromatography-tandem mass spectrometry

To circumvent the limitations of current antidepressants, WJ-14, a novel N-methyl-d-aspartate receptor antagonist, was synthesized and demonstrated to have remarkable efficiency in the treatment of depression. To illustrate the pharmacokinetics, absolute bioavailability, and tissue distribution of WJ-14 in rats, a rapid and sensitive liquid chromatography-tandem mass spectrometry-based analytical method was developed and validated for the separation and detection of WJ-14 in both plasma and tissue samples. After oral administration, WJ-14 was rapidly absorbed into the blood with time to reach the maximum plasma concentration (Tmax ) within 0.28 h and quickly eliminated with clearance (Cl) exceeding 6.80 L/h/kg and elimination half-life (t1/2 ) within 2.69 h. No obvious accumulation was found with mean residencetime (MRT) within 4.10 h. Tissue distribution revealed that WJ-14 was extensively distributed in the main tissues of rats, and massive amounts of WJ-14 were distributed in the liver. Extensive distribution and quick elimination led to extremely low absolute bioavailability of WJ-14 (1.91% of 8.33 mg/kg and 3.30% of 24.99 mg/kg). WJ-14 was detected in the brain only 0.083 h after oral administration, which is crucial for a rapid-onset antidepressant candidate. In addition, WJ-14 likely exhibited a non-linear pharmacokinetic process at dosages of 8.33 and 24.99 mg/kg. The findings may provide valuable information for subsequent studies on WJ-14.

Tryptophanol-Derived Oxazolopyrrolidone Lactams as Potential Anticancer Agents against Gastric Adenocarcinoma

Gastric cancer is one of the deadliest cancers in modern societies, so there is a high level of interest in discovering new drugs for this malignancy. Previously, we demonstrated the ability of tryptophanol-derived polycyclic compounds to activate the tumor suppressor protein p53, a relevant therapeutic target in cancer. In this work, we developed a novel series of enantiomerically pure tryptophanol-derived small molecules to target human gastric adenocarcinoma (AGS) cells. From an initial screening of fourteen compounds in AGS cell line, a hit compound was selected for optimization, leading to two derivatives selective for AGS gastric cells over other types of cancer cells (MDA-MB-231, A-549, DU-145, and MG-63). More importantly, the compounds were non-toxic in normal cells (HEK 293T). Additionally, we show that the growth inhibition of AGS cells induced by these compounds is mediated by apoptosis. Stability studies in human plasma and human liver microsomes indicate that the compounds are stable, and that the major metabolic transformations of these molecules are mono- and di-hydroxylation of the indole ring.