The 17-oxo analogs of the heteroaromatic steroids were also prepared by Jones oxidation. also determined using non-cancerous MRC-5 cells. Furthermore, TG 003 the proapoptotic effects of some selected derivatives were verified on androgen therapy refractive p53-deficient PC-3 cells. The present study concludes that novel DHT-derived arylpyrazoles exert malignancy cell specific antiproliferative activity and activate apoptosis in Personal computer-3 cells. . In spite of the obvious truth the incorporation of different heterorings to 2,3 position of DHT and to its analogs may significantly alter the bioactivity of the parent molecule, very few good examples are to be found in the literature for such kind of transformations. In this respect, we previously shown that different heteroaryl-fused derivatives of DHT exert significant antiproliferative effect in vitro on human being tumor cell lines of varied origins Rabbit Polyclonal to UBF (phospho-Ser484) [21,22,23]. Open in a separate window Number 1 Ring-A condensed heterocyclic derivatives of dihydrotestosterone (DHT) with designated biological activities. In view of the potential biological significance of heterocyclic DHT analogs, and the well-known antiproliferative potential of numerous steroids comprising pyrazoline or pyrazole scaffolds [24,25,26,27], we now describe a facile, one-pot heterocyclization/oxidation sequence of a DHT-derived steroidal enone with different arylhydrazines in the presence of iodine under microwave (MW) conditions. The stepwise sequence, i.e., the cyclocondensation of the unsaturated ketone to pyrazolines, and the subsequent oxidation to pyrazoles was also investigated. Finally, the 17-keto derivatives were synthesized as well in order to enlarge the compound library available for pharmacological studies. All the synthesized compounds were primarily screened in vitro for his or her antiproliferative activity on five different malignancy cell lines, namely DU 145, Personal computer-3, HeLa, MCF-7 and MDA-MB-231 and on non-cancerous MRC-5 fibroblasts. Our results indicate that several compounds show tumor cell specific and dose dependent inhibition of cell growth. Based on these data, five compounds featuring outstanding TG 003 tumor cell specificity were selected for further experiments i.e., to determine IC50 ideals. Annexin VCpropidium iodide staining and quantitative-real time PCR were TG 003 performed to examine in details the proapoptotic activity of selected ring A-fused arylpyrazole derivatives of DHT on androgen therapy refractive p53 deficient Personal computer-3 cells. 2. Results and Discussion 2.1. Synthetic Studies For the synthesis of steroidal ring A-fused pyrazole derivatives, DHT was first subjected to aldol condensation with an excess of acetaldehyde in alkaline ethanol at low temp in order to obtain the starting ,-enone suitable for heterocyclization. Even though related aldol-type ClaisenCSchmidt reaction of cyclic ketones with different arylaldehydes is frequently applied for the efficient synthesis of arylidene ketones [28,29], the use of acetaldehyde is fairly unusual due to its higher reactivity and ability to undergo undesirable self-condensation . Nevertheless, the transformation led to the regioselective formation of 2-ethylidene-DHT (1) in good yield (70%) after purification by column chromatography (Table 1). The expected (E)-construction along the double relationship was evidenced by NOESY correlations between the 1-H and 21-CH3 protons (Supplementary Material). Table 1 Yields of ring A-fused arylpyrazole derivatives of DHT acquired by Method C (4aCj) and subsequent oxidation (5aCj). = 7.2 Hz, = 2.2 Hz, 21-H3), 1.84 (d, 1H, = 15.2 Hz, 1-H), 1.87 (m, 1H), 2.06 (m, 1H, 16-H), 2.14 (dd, 1H, = 18.5 Hz, = 13.2 Hz, 4-H), 2.33 (dd, 1H, = 18.5 Hz, = 5.2 Hz, 4-H), 2.76 (d, 1H, = 15.2 Hz, 1-H), 3.65 (t, 1H, = 8.6 Hz, 17-H), 6.74 (m, 1H, 20-H); 13C NMR (CDCl3, 125 MHz): 11.0 (C-18), 11.8 (C-19), 13.6 (C-21), 20.9 (C-11), 23.4 (C-15), 28.4 (C-6), 30.5 (C-16), 31.0 (C-7), 35.4.