SN38n

SN38n is a designation that does not correspond to a widely recognized chemical entity in major public databases or standard pharmacological references. In many cases, the well-known compound related to this name is SN-38, the active metabolite of the anticancer prodrug irinotecan (CPT-11), a potent inhibitor of topoisomerase I. If SN38n appears in the literature, it may reflect a few possibilities: it could be an alternate name for SN-38 in a specific study, a derivative or label used by a research group, or a typographical error for SN-38 or SN-38 glucuronide (SN-38G). Without a defined chemical structure or accompanying data, the properties, synthesis, and biological activity of SN38n cannot be stated reliably.

SN-38, produced by hepatic and intestinal carboxylesterases from irinotecan, is markedly more potent than irinotecan itself. It exerts cytotoxic effects by stabilizing the topoisomerase I-DNA complex, leading to DNA strand breaks in proliferating cells. The lactone ring of SN-38 is essential for activity, but tends to hydrolyze to an inactive carboxylate form at physiological pH. Metabolically, SN-38 is mainly detoxified by glucuronidation through UGT1A1 to SN-38G, a process subject to genetic variation that can influence toxicity and response.

Research into SN-38 derivatives and formulations, such as prodrugs, liposomal encapsulation, and polymer conjugates, aims to improve solubility, pharmacokinetics, and tolerability, while preserving topoisomerase I inhibition. If SN38n is encountered in a particular study, it should be examined for its explicit chemical identity, structure, and context to determine whether it represents a true new entity or a mislabeling of an established SN-38 form.

See also: Irinotecan, SN-38, SN-38G, Topoisomerase I inhibitors.