Anti-inflammatory hybrids of secondary amines and amide-sulfamide derivatives

Abstract

The CXCR4/CXCL12 chemokine axis can chemotactically accumulate inflammatory cells to local tissues and regulate the release of inflammatory factors. Developing novel CXCR4 modulators may provide a desirable strategy to control the development of inflammation. A series of novel hybrids were designed by integrating the key pharmacophores of three CXCR4 modulators. The majority of compounds displayed potent CXCR4 binding affinity. Compound 7a exhibited 1000-fold greater affinity than AMD3100 and significantly inhibited invasion of CXCR4-positive tumor cells. Additionally, compound 7a blocked mice ear inflammation by 67% and suppressed the accumulation of inflammatory cells in an in vivo mouse ear edema evaluation. Western blot analyses revealed that 7a inhibited the CXCR4/CXCL12-mediated phosphorylation of Akt and p44 in a dose-dependent manner. Moreover, compound 7a had no observable cytotoxicity and displayed a favorable plasma stability in our preliminary pharmacokinetic study. These results confirmed that this is a feasible method to develop CXCR4 modulators for the regulation and reduction of inflammation.

Development of CXCR4 modulators based on the lead compound RB-108

“…All of the prepared compounds were first screened with a binding affinity assay as described in our previous publications [18][19][20][21][22][23]. The screening protocol is a competitive CXCR4 binding assay between biotinylated TN14003, a potent CXCR4 peptidic antagonist, and the target compounds Ia-b, IIa-c, and IIIa-o at concentrations of 1, 10, 100, and 1000 nM.…”

“…The slides were subsequently incubated for 30 minutes at room temperature with 0.05 μg/mL biotinylated TN14003, washed three times with PBS, and incubated in streptavidin-rhodamine (1:150 dilution; Jackson ImmunoResearch Laboratories, West Grove, PA) for 30 minutes at room temperature. Finally, the slides were washed with PBS and mounted in an anti-fade mounting solution (Molecular Probes, Eugene, OR), and the samples were analyzed on a Nikon Eclipse E800 microscope [18][19][20][21][22][23]26].…”

“…Invading cells on the filter at the bottom of the Matrigel were fixed in methanol and stained with hematoxylin and eosin (H & E). The percent of invasion was determined by counting the H&E stained cells [18][19][20][21][22][23].…”

“…Taking AMD3100 as the lead compound, our research group discovered a series of promising bis-secondary amines as potent CXCR4 antagonist, including Q-122, a CXCR4 modulator which is now under Phase IIb clinical trials on neuroinflammation indication [17]. Further structural modification and optimization of the two secondary amine groups lead to the discovery of the second generation of CXCR4 modulators, the amide-sulfamide compounds [18,19]. Among these amide-sulfamide derivatives, RB-108 displayed potent in vitro and in vivo anti-inflammatory activity and was selected as our lead compound.…”

Fragmentation pathways of deprotonated amide‐sulfonamide CXCR4 inhibitors investigated by ESI‐IT‐MSn, ESI‐Q‐TOF‐MS/MS and DFT calculations

“…The CXCL12/CXCR4 axis has been shown to be involved in cancer metastasis and inflammation . The amide‐sulfonamide scaffold is a novel class of CXCR4 inhibitors developed by our research group, which exhibited promising anti‐inflammatory effect both in vitro and in vivo . Taking RB‐108 (compound 9 ) as an example, this amide‐sulfonamide compound demonstrated potent binding affinity to CXCR4 at the concentration of only 1 nM and significantly inhibited the mice ear inflammation and damage …”