Synthesis and Antiproliferative Potential of Thiazole and 4-Thiazolidinone Containing Motifs as Dual Inhibitors of EGFR and BRAFV600E.

Thiazole and thiazolidinone recur in a wide range of biologically active compounds that reach different targets within the context of tumors and represent a promising starting point to access potential candidates for treating metastatic cancer. Therefore, searching for new lead compounds that show the highest anticancer potency with the fewest adverse effects is a major drug-discovery challenge. Because the thiazole ring is present in dasatinib, which is currently used in anticancer therapy, it is important to highlight the ring. In this study, cycloalkylidenehydrazinecarbothioamides (cyclopentyl, cyclohexyl, cyclooctyl, dihydronapthalenylidene, flurine-9-ylidene, and indolinonyl) reacted with 2-bromoacetophenone and diethylacetylenedicarboxylate to yield thiazole and 4-thiazolidinone derivatives. The structure of the products was confirmed by using infrared (IR) spectroscopy, nuclear magnetic resonance (NMR) spectroscopy, mass spectrometry, and single-crystal X-ray analyses. The antiproliferative activity of the newly synthesized compounds was evaluated. The most effective inhibitory compounds were further tested in vitro against both epidermal growth factor receptor (EGFR) and B-Raf proto-oncogene, serine/threonine kinase (BRAFV600E) targets. Additionally, molecular docking analysis examined how these molecules bind to the active sites of EGFR and BRAFV600E.

Crystal structure of 1-(cyclo-pentyl-idene-amino)-3-(prop-2-en-1-yl)thio-urea.

In the title compound, C9H15N3S, the cyclo-pentyl ring adopts an envelope conformation with one of the methyl-ene C atoms as the flap. The thio-semicarbazide fragment is almost planar (r.m.s. deviation = 0.038 Å) and a short intra-molecular N-H⋯N contact occurs. In the crystal, mol-ecules are linked into helical (41 symmetry) chains propagating in [001] by N-H⋯N and N-H⋯S hydrogen bonds. A very weak C-H⋯S inter-action is also observed.

Crystal structure of 3-benzyl-1-[(cyclo-hexyl-idene)amino]-thio-urea.

The conformation of the title compound, C14H19N3S, is partially determined by an intra-molecular N-H⋯N hydro-gen-bond inter-action, although the N-H⋯N angle of 108° is quite small. The cyclo-hexyl-idene ring has a chair conformation and its mean plane is inclined to the benzene ring by 46.30 (8)°. In the crystal, mol-ecules are linked by pairs of N-H⋯S hydrogen bonds, forming inversion dimers, with an R 2 (2)(8) ring motif. The dimers are reinforced by pairs of C-H⋯S hydrogen bonds, and are linked by further weak C-H⋯S hydrogen bonds, forming chains propagating along [100].

Crystal structure of 3-benzyl-1-[(1,2,3,4-tetra-hydro-naphthalen-1-yl-idene)amino]-thio-urea.

In the title compound, C18H19N3S, the dihedral angle between the planes of the benzene rings is 58.63 (8)°. The six-membered ring bonded to the thio-semicarbazide group (r.m.s. deviation = 0.038 Å) adopts a sofa conformation, with one of the methyl-ene-group C atoms as the flap. A short intra-molecular N-H⋯N contact is observed. In the crystal, mol-ecules are linked by weak N-H⋯S inter-actions to generate C(4) chains propagating in the [010] direction, with adjacent mol-ecules related by glide symmetry.

Crystal structure of 3-(prop-2-en-1-yl)-1-{[(1E)-1,2,3,4-tetra-hydro-naphthalen-1-yl-idene]amino}-thio-urea.

In the title compound, C14H17N3S, the dihedral angle between the planes of the benzene ring and the thio-semicarbazone group (r.m.s. deviation = 0.031 Å) is 8.45 (4)°. A short intra-molcular N-H⋯N contact is seen. In the crystal, weak N-H⋯S hydrogen bonds connect the mol-ecules into C(4) chains propagating in the [010] direction, with adjacent mol-ecules in the chain related by 21 screw-axis symmetry.

The effect of curcumin on insulin release in rat-isolated pancreatic islets.

Curcumin exerts a hypoglycemic action and induces heme-oxygenase-1 (HO-1). We evaluated the effect of curcumin on isolated islets of Langerhans and studied whether its action on insulin secretion is mediated by inducible HO-1. Islets were isolated from rats and divided into control islets, islets incubated in different curcumin concentrations, islets incubated in hemin, islets incubated in curcumin and HO inhibitor, stannous mesoporphyrin (SnMP), islets incubated in hemin and SnMP, islets incubated in SnMP only, and islets incubated in 16.7 mmol/L glucose. Heme-oxygenase activity, HO-1 expression, and insulin estimation was assessed. Insulin secretion, HO-1 gene expression and HO activity were significantly increased in islets incubated in curcumin, hemin, and glucose compared with controls. This increase in insulin secretion was significantly decreased by incubation of islets in SnMP. The action of curcumin on insulin secretion from the isolated islets may be, in part, mediated through increased HO-1 gene expression.

Effect of hemin and carbon monoxide releasing molecule (CORM-3) on cGMP in rat penile tissue.

INTRODUCTION: Cyclic guanosine monophosphate (cGMP) levels can be regulated by heme oxygenase-1 and 2 (HO-1 and HO-2)-derived carbon monoxide (CO). AIMS: Assessment of the effect of upregulating CO in rat corpora cavernosa (CC) on cavernous cGMP. METHODS: Three experimental groups were studied: first group (N = 40), short-term HO induction over 2 weeks by injection of intraperitoneal increasing doses of hemin; the second group (N = 40) was subjected to intracavernosal injection of CO donor, CORM-3, or its inactive form (iCORM-3) over 2 weeks; the third group (N = 60) was subdivided into three subgroups: the first one received a combined hemin and CORM-3, the second one received hemin and its inhibitor stannus mesoporphyrin (SnMP), and third one received a combined hemin, CORM-3, and SnMP. MAIN OUTCOME MEASURES: In CC, HO-1 and HO-2 gene expression, Northern blot and Western blot, cGMP levels, and HO enzyme activity. RESULTS: In the first group, maximum induction of HO-1 gene expression, HO enzyme activity, and cGMP occurred with 4-mg hemin dose with a successive increase over 2 weeks. In the second group, CORM-3 increased cGMP by twofold compared with iCORM-3, and also increased HO-1 protein. In the third group, SnMP inhibited the enhancing effect of CORM-3 and HO on erectile signaling molecules; i.e., HO-1 gene, enzyme activity, and cGMP. CONCLUSIONS: CORM-3- or hemin-mediated CO release could increase cavernous tissue cGMP.