D-420720, A novel orally active sulfonamide compound dipeptidyl peptidase IV inhibitor: structure and activity relationship of arylsulfonamide to dipeptidyl peptidase IV inhibition

Synthesis of β-Amino Carbonyl 6-(Aminomethyl)- and 6-(Hydroxymethyl)pyrazolopyrimidines for DPP-4 Inhibition Study

BACKGROUND

Type-2 diabetes is a chronic progressive metabolic disease resulting in severe vascular complications and mortality risk. Recently, DPP-4 inhibitors had been conceived as a favorable class of agents for the treatment of type 2 diabetes due to the minimal side effects.

METHODS

Sitagliptin is the first medicine approved for the DPP-4 inhibitor. Its structure involved three fragments: 2,4,5-triflorophenyl fragment pharmacophore, enantiomerically β-amino carbonyl linker, and tetrahydrotriazolopyridine. Herein, we are drawn to the possibility of substituting tetrahydrotriazolopyridine motif present in Sitagliptin with a series of new fused pyrazolopyrimidine bicyclic fragment to investigate potency and safety.

RESULTS

Two series of fused 6-(aminomethyl)pyrazolopyrimidine and 6-(hydroxymethyl) pyrazolopyrimidine derivatives containing β-amino ester or amide as linkers were successfully designed for the new DPP-4 inhibitors. Most fused 6-methylpyrazolopyrimidines were evaluated against DPP-4 inhibition and selectivity capacity. Based on research study, β-amino carbonyl fused 6-(hydroxymethyl)pyrazolopyrimidine possesses the significant DPP-4 inhibition (IC50 ≤ 59.8 nM) and presents similar with Sitagliptin (IC50 = 28 nM). Particularly, they had satisfactory selectivity over DPP-8 and DPP-9, except for QPP.

CONCLUSION

β-Amino esters and amides fused 6-(hydroxymethyl)pyrazolopyrimidine were developed as the new DPP-4 inhibitors. Those compounds with a methyl group or hydrogen in N-1 position and methyl substituted group in C-3 of pyrazolopyrimidine moiety showed better potent DPP-4 inhibition (IC50 = 21.4-59.8 nM). Furthermore, they had satisfactory selectivity over DPP-8 and DPP-9 Finally, the docking results revealed that compound 9n was stabilized at DPP-4 active site and would be a potential lead drug.

Recent Medicinal Chemistry Approach for the Development of Dipeptidyl Peptidase IV Inhibitors

BACKGROUND

Diabetes, a metabolic disease, occurs due to a decreased or no effect of insulin on the blood glucose level. The current oral medications stimulate insulin release, increase glucose absorption and its utilization, and decrease hepatic glucose output. Two major incretin hormones like Glucose-dependent insulinotropic polypeptide (GIP) and glucagonlike peptide - 1 (GLP-1) stimulate insulin release after a meal, but their action is inhibited by enzyme dipeptidyl peptidase- IV.

OBJECTIVE

The activity of endogenous GLP-1 and GIP prolongs and extends with DPP IV inhibitors, which are responsible for the stimulation of insulin secretion and regulation of blood glucose level. DPP IV inhibitors have shown effectiveness and endurability with a neutral effect on weight as well as less chances of hypoglycemia in the management of type 2 diabetes. These journeys started from Sitagliptin (marketed in 2006) to Evogliptin (marketed in 2015, Korea).

CONCLUSION

Treatment of type 2 diabetes includes lifestyle changes, oral medications, and insulin. Newer and superior therapies are needed more than currently prescribed drugs. Various heterocyclic derivatives have been tried, but due to masking of DASH proteins, CYP enzymes, and hERG channel, they showed side effects. Based on these, the study has been focused on the development of safe, influential, selective, and long-lasting inhibitors of DPP IV.

Design, Synthesis, Activity and Docking Study of Sorafenib Analogs Bearing Sulfonylurea Unit

Two series of novel sorafenib analogs containing a sulfonylurea unit were synthesized and their chemical structures were confirmed by ¹H-NMR, ¹³C-NMR, MS spectrum and elemental analysis. The synthesized compounds were evaluated for the cytotoxicity against A549, Hela, MCF-7, and PC-3 cancer cell lines. Some of the compounds showed moderate cytotoxic activity, especially compounds 1-(2,4-difluorophenylsulfonyl)-3-(4-(2-(methylcarbamoyl)pyridin-4-yloxy)phenyl)urea (6c) and 1-(4-bromophenylsulfonyl)-3-(4-(2-(methylcarbamoyl)pyridin-4-yloxy)phenyl)urea (6f) with the IC₅₀ values against four cancer cell lines ranging from 16.54 ± 1.22 to 63.92 ± 1.81 μM, respectively. Inhibitory rates against vascular endothelial growth factor receptor-2 (VEGFR2/KDR) kinase at 10 μM of target compounds were further carried out in this paper in order to investigate the target of these compounds. Structure-activity relationships (SARs) and docking studies indicated that the sulfonylurea unit was important to these kinds of compounds. None of the substitutions in the phenoxy group and small halogen atoms such as 2,4-difluoro substitution of the aryl group contributed to the activity. The results suggested that sulfonylurea sorafenib analogs are worthy of further study.

Design, Synthesis, and Biological Evaluation of Sorafenib Analogs Bearing a Sulfonylurea Unit as Novel VEGFR2 Kinase Inhibitors

Two sorafenib analogs (9a,9b) containing sulfonylurea unit were synthesized and their chemical structures were confirmed by 1H NMR and MS spectrum. The synthesized compounds were evaluated for the inhibition rate against VEGFR2 kinase at 10μM level. The inhibition rates of compound 9a and 9b against VEGFR2 kinase were 61.0±11.1% and 22.6±2.6%, respectively. The results showed that the introduction of sulfonylurea unit is favorable for the activity, and further study is being carried out.