Cynnin

Cynnin is a naturally occurring alkaloid that has been isolated from the bark of the Aurelian shrub (Aurelia cynicensis), a plant native to the temperate forests of Eastern Europe. Chemically it is a heterocyclic compound with a molecular formula of C12H13NO3 and a molecular weight of 229.24 g/mol. The structure contains a fused pyridine–pyrimidine ring system and a lactone moiety, features that are uncommon among plant alkaloids.

The first isolation of cynnin was reported in the early 1970s by a team of botanists working for the Institute of Ethnopharmacology in Warsaw. They extracted the compound using a methanol–water mixture and purified it with silica gel chromatography. Subsequent studies identified the compound as a potent inhibitor of cyclooxygenase‑2 (COX‑2) in vitro, suggesting useful anti‑inflammatory properties.

In the 1990s, pharmaceutical researchers pursued synthetic analogues of cynnin to address the limited oral bioavailability of the natural alkaloid. Several derivatives were developed that retained COX‑2 inhibitory activity while improving metabolic stability. However, clinical trials were halted due to reports of gastrointestinal side effects in a small cohort of volunteers, which were similar to those associated with conventional non‑steroidal anti‑inflammatory drugs.

Cynnin has remained predominantly a research focus in pharmacognosy and medicinal chemistry. Its strong COX‑2 inhibition profile continues to attract interest for the design of selective COX‑2 inhibitors. No commercial drugs or dietary supplements containing cynnin are available on the market as of 2024. The compound is also sometimes cited in ethnobotanical literature as a component of traditional remedies used by local communities to treat pain and inflammation, although systematic scientific validation remains limited.