332131-32-5

Protein tyrosine phosphatases (PTPs) remove phosphate from tyrosine residues of cellular proteins. Reversible phosphorylation catalyzed by the coordinated actions of protein tyrosine kinases and phosphatases is key to the regulation of the signaling events that control cell growth and proliferation, differentiation, and survival or apoptosis, as well as adhesion and motility. RK-682, a bioactive compound originally isolated from the fermentation of Streptomyces sp. 88-682, is an inhibitor of the PTPs. It inhibits the phosphorylation of CD45 and VHR with IC₅₀ values of 54 and 2 μM, respectively, and arrests cell cycle progress at the G₁/S transition. It is also reported to inhibit heparanase (IC₅₀ = 17 μM), an endo-β-D-glucuronidase involved in tumor cell invasion and angiogenesis. RK-682 (calcium salt) is a less soluble version of the free acid.

RK-682 is a dimeric calcium complex of the major analogue of a tetronic acid complex isolated from Streptomyces. Although reported by researchers at RIKEN in 1995, subsequent synthesis in 2001 showed that RK-682 was in fact the calcium complex formed during silica chromatography. Confusion about the structure of RK-682 has lead to the monomeric sub-unit, TAN 1364B (3-hexadecanoyl-5-hydroxymethyltetronic acid) being mis-named as RK-682 by many suppliers. As either the dimer or monomer, RK-682 inhibits protein tyrosine phosphatases, phospoholipase A2, heparinase and HIV-1 protease. However, is unclear whether biological activity is due to the monomer (TAN 1364B) or dimeric complex (RK-682).

RK-682 is a dimeric calcium complex of the major analogue of tetronic acid complex isolated from Streptomyces. Although reported by researchers at RIKEN in 1995, subsequent synthesis in 2001 showed that RK-682 was in fact the calcium complex formed during silica chromatography. Confusion about the structure of RK-682 has lead to the monomeric sub-unit, TAN 1364B (3-hexadecanoyl-5-hydroxymethyltetronic acid) being mis-named as RK-682 by many suppliers. As either the dimer or monomer, RK 682 inhibits protein tyrosine phosphatases, phospoholipase A2, heparinase and HIV-1 protease. However, is unclear whether biological activity is due to the monomer (TAN 1364B) or dimeric complex (RK-682).

RK-682 is a specific PTP1B inhibitor.

[1] TAKUYA HAMAGUCHI  Hiroyuki O  Tatsuhiko Sudo. RK-682, a potent inhibitor of tyrosine phosphatase, arrested the mammalian cell cycle progression at G1phase[J]. FEBS Letters, 1995, 372 1: Pages 54-58. DOI: 10.1016/0014-5793(95)00953-7
[2] KEISUKE ISHIDA. Structure-based design of a selective heparanase inhibitor as an antimetastatic agent.[J]. Molecular Cancer Therapeutics, 2004, 3 9: 1069-1077.
[3] M. SODEOKA. Asymmetric synthesis of a 3-acyltetronic acid derivative, RK-682, and formation of its calcium salt during silica gel column chromatography.[J]. Chemical & pharmaceutical bulletin, 2001, 40 1: 206-212. DOI: 10.1248/cpb.49.206