Catechol O‑Methyl Transferase (COMT, HEL-S-98n) degrades catecholamines, catecholestrogens and various drugs having a catechol structure. Mutation of COMT is associated with obsessive-compulsive disorder in men, anxiety phenotypes in women, schizophrenia and other. Developing of the COMT inhibitors is a promising area of neuropsychiatric research. Also catechol‐O‐methyltransferase inhibitors are used as adjuvants to the levodopa/AADC inhibitor therapy for Parkinson's disease treatment.

Enhancer of zeste homolog 2 (EZH2, ENX-1, ENX1, EZH1, EZH2b, KMT6, KMT6A, WVS, WVS2, enhancer of zeste 2 polycomb repressive complex 2 subunit) is a histone-lysine N-methyltransferase. This enzyme plays an important role in histone methylation and, ultimately, transcriptional repression.

Mutation or over-expression of EZH2 has been linked to many forms of cancer, including bladder, uterine, breast, prostate and renal cancers. EZH2 inhibits genes responsible for suppressing of tumor development, and blocking of it activity may slow tumor growth. Therefore, EZH2 is an attractive target for anti-cancer therapy.