1375262-93-3Relevant articles and documents
Discovery of imidazoquinolines with toll-like receptor 7/8 independent cytokine induction
Shi, Ce,Xiong, Zhengming,Chittepu, Padmaja,Aldrich, Courtney C.,Ohlfest, John R.,Ferguson, David M.
, p. 501 - 504 (2012)
Toll-like receptors (TLRs) are key targets in the design of immunomodulating agents for use as vaccine adjuvants and anticancer treatments. The imidazoquinolines, imiquimod and resiquimod, have been shown to activate TLR-7 and -8, which in turn induce cytokine production as part of the innate immune response. Herein, we report the synthesis and discovery of a C7-methoxycarbonyl derivative of imiquimod that stimulates cytokine production but is devoid of TLR-7/8 activity. Data are presented that shows that this analogue not only induces IL-12p40 and TNF production, similar to that of imiquimod and resiquimod, but greatly enhances the production of IL-1β, a key cytokine involved in the activation of CD4 T cells. It is further demonstrated that TLR-7/8 activation can be recovered by the addition of a C2-alkyl substituent to this newly discovered analogue. The results support the existence of an alternative mechanism of action by which imidazoquinolines can stimulate cytokine production.
Structure-activity relationship analysis of imidazoquinolines with toll-like receptors 7 and 8 selectivity and enhanced cytokine induction
Schiaffo, Charles E.,Shi, Ce,Xiong, Zhengming,Olin, Michael,Ohlfest, John R.,Aldrich, Courtney C.,Ferguson, David M.
, p. 339 - 347 (2014/02/14)
Toll-like receptors 7 and 8 (TLRs) have emerged as key targets in the design of small molecule adjuvants and stimulants for use in immunotherapies. This study examines the structure-activity relationship of a series of C2- and N1-substituted C7-methoxycarbonylimidazoquinolines to gain insight to the structural basis to TLR-7 and -8 selective activity. The analysis is further applied to evaluate the induction of multiple cytokines, including IL-10, IL-12, IL-1β, TNF-α, IFN-α, and IFN-γ, using murine BMDCs and human PBMCs. The results show TLR-7/8 activity is correlated to the C2-alkyl chain length, with peak activity occurring for the butyl (TLR-7) and pentyl (TLR-8) derivatives. A similar SAR is identified in the production of IL-1β, IL-12, and IFN-γ, which are shown to depend on both the C2-alkyl chain length and substitution to the N1-position. The compounds were also potent stimulators of IFN-α and IL-10 production but with less pronounced structure-based correlations.
