Design and synthesis of an indol derivative as antibacterial agent against Staphylococcus aureus.

Several indole derivatives with antibacterial activity have been prepared using different protocols; however, some require special reagents and conditions. The aim of this study involved the synthesis of some indole derivatives using estrone and OTBS-estrone as chemical tools. The synthesis of the indole derivatives involves reactions such as follows: (1) synthesis of two indol derivatives (4 or 5) by reaction of estrone or OTBS-estrone with phenylhydrazine in medium acid; (2) reaction of 4 or 5 with 6-cloro-1-hexyne in medium basic to form two hexynyl-indol (7 or 8); (3) preparation of indol-propargylic alcohol derivatives (10 or 11) by reaction of benzaldehyde with 7 or 8 in medium basic; (4) synthesis of indol-aldehydes (12 or 13) via oxidation of 10 or 11 with DMSO; (5) synthesis of indeno-indol-carbaldehyde (15 or 16) via alkynylation/cyclization of 12 or 13 with hexyne in presence of copper(II); (6) preparation indeno-indol-carbaldehyde complex (19 or 20) via alkynylation/cyclization of 12 or 13 with 1-(hex-5-yn-1-yl)-2-phenyl-1H-imidazole. The antibacterial effect exerted by the indol-steroid derivatives against Streptococcus pneumoniae and Staphylococcus aureus bacteria was evaluated using dilution method and the minimum inhibitory concentration (MIC). The results showed that only the compound 19 inhibit the growth bacterial of S. aureus. In conclusion, these data indicate that antibacterial activity of 19 can be due mainly to functional groups involved in the chemical structure in comparison with the compounds studied.

Design and synthesis of four steroid-oxirane derivatives using some chemical tools.

This study involved the synthesis of several new derivatives of progesterone, 11a-hydroxyprogesterone, 11a-t-butyldimethylsilanyloxyprogesterone, and andrenosterone. The new derivatives were prepared by condensation of the 4-en-3-one moiety of the four steroids with 2-hydroxy-1-naphthaldehyde to afford a series of 4-(R)-hydroxy-(2-hydroxynaphtalen-1-yl) adducts. These adducts were further modified by cyclization reactions of the dihydroxynaphthalenyl moieties with succinic acid, and the resulting cyclic succinates were then condensed with ethylenediamine to form imine derivatives at all available carbonyl groups. These compounds were then derivatized by N-acylation of the 11- and 17-imine nitrogens with chloroacetyl chloride and the resulting chloroacetamides were then condensed with 2-hydroxy-1-napthaldehyde in Darzens-type reactions forming the corresponding epoxy acetamides in the side chains. In addition, the chemical structure of steroid derivatives was confirmed by NMR spectroscopic data.

Evaluation of activity of an estrogen-derivative as cardioprotector drug using an ischemia-reperfusion injury model.

Myocardial ischemia/reperfusion injury is a serious problem involved in cardiovascular diseases. There data which indicate that some steroids induce cardioprotective effects on myocardial ischemia-reperfusion injury; however their activity and the molecular mechanism involved on myocardial ischemia-reperfusion injury are very confusing. Therefore, in this study some estrogen derivatives (compound 3 to 7) were synthesized with the objective of evaluating its activity on myocardial ischemia/reperfusion injury using an isolated heart model. Additionally, molecular mechanism involved in the activity exerted by the compounds 3 to 7 on perfusion pressure and coronary resistance was evaluated by measuring left ventricular pressure in absence or presence of following compounds; prazosin, metoprolol, indomethacin and nifedipine. The results showed that 7 reduce infarct size compared with the estrone and other estrogen derivatives (compounds 3, 4, 5, and 6). Other results showed that 7 significantly increase the perfusion pressure and coronary resistance in isolated heart in comparison with estrone, 3, 4, 5, and 6. Finally, other data indicate that 7 increased the left ventricular pressure in a dose-dependent manner; however, this phenomenon was significantly inhibited by nifedipine. In conclusion, all these data suggest that 7 exert a cardioprotective effect through calcium channels activation and consequently induce changes in the left ventricular pressure levels. This phenomenon results in decrease of myocardial necrosis after ischemia and reperfusion.

Design and synthesis of new dihydrotestosterone derivative with positive inotropic activity.

There are several reports which indicate that some steroid derivatives have inotropic activity; nevertheless, the cellular site and mechanism of action of steroid derivatives at cardiovascular level is very confusing. In order, to clarify these phenomena in this study, two dihydrotestosterone derivatives (compounds 5 and 10) were synthesized with the objective of to evaluate its biological activity on left ventricular pressure and characterize their molecular mechanism. In the first stage, the Langendorff technique was used to measure changes on perfusion pressure and coronary resistance in an isolated rat heart model in absence or presence of the steroid derivatives. Additionally, to characterize the molecular mechanism involved in the inotropic activity induced by the compound 5 was evaluated by measuring left ventricular pressure in absence or presence of following compounds; nifedipine, flutamide, indomethacin, prazosin, isoproterenol, propranolol and metoprolol. The results showed that the compound 5 significantly increased the perfusion pressure and coronary resistance in comparison with dihydrotestosterone, compound 10 and the control conditions. Other data indicate that 5 increase left ventricular pressure in a dose-dependent manner (0.001-100 nM); nevertheless, this phenomenon was significantly inhibited only by propranolol or metoprolol at a dose of 1 nM. These data suggest that positive inotropic activity induced by the compound 5 is through ß1-adrenergic receptor however, this effect was independent of cAMP levels. This phenomenon is a particularly interesting because the positive inotropic activity induced by this steroid derivative involves a molecular mechanism different in comparison with other positive inotropic drugs.

Synthesis and antibacterial activity evaluation of two androgen derivatives.

In this study two androgen derivatives were synthesized using several strategies; the first stage an aza-steroid derivative (3) was developed by the reaction of a testosterone derivative (1) with thiourea (2) in presence of hydrogen chloride. The second step, involves the synthesis of an amino-steroid derivative (4) by the reaction of 1 with 2 using boric acid as catalyst. The third stage was achieved by the preparation of an aminoaza-androgen derivative (6) by the reaction of 3 with ethylenediamine using boric acid as catalyst. In addition, the compound 6 was made reacting with dihydrotestosterone to form a new androgen derivative (7) in presence of boric acid. The following step was achieved by the reaction of 7 with chloroacetyl chloride to synthesize an azetidinone-androgen derivative (8) using triethylamine as catalyst. Additionally, a thiourea-androgen derivative (9) was synthetized by the reaction of 4 with dihydrotestosterone using boric acid as catalyst. Finally, the compound 9 was made reacting with chloroacetyl chloride in presence of triethylamine to synthesize a new azetidinone-androgen derivative (10). On the other hand, antibacterial activity of compounds synthesized was evaluated on Gram negative (Escherichia coli and Vibrio cholerae) and Gram positive (Staphylococos aureus) bacteria. The results indicate that only the compound 3 and 8 decrease the growth bacterial of E. coli and V. cholerae. Nevertheless, growth bacterial of S. aureus was not inhibited by these compounds. These data indicate that antibacterial activity exerted by the compounds 3 and 8 depend of their structure chemical in comparison with the controls and other androgen derivatives that are involved in this study.

Evaluation of activity inotropic of a new steroid derivative using an isolated rat heart model.

There are studies which indicate that some steroid derivatives have inotropic activity; nevertheless, the cellular site and mechanism of action at cardiovascular level is very confusing. In order, to clarify these phenomena in this study, a new estradiol derivative was synthesized with the objective of to evaluate its biological activity on left ventricular pressure and characterize their molecular mechanism. The Langendorff technique was used to measure changes on perfusion pressure and coronary resistance in an isolated rat heart model in absence or presence of the estradiol derivative. Additionally, to characterize the molecular mechanism involved in the inotropic activity induced by the OTBDS-estradiol-hexanoic acid derivative was evaluated by measuring left ventricular pressure in absence or presence of following compounds; tamoxifen, prazosin, metoprolol, indomethacin and nifedipine. The results showed that the OTBDS-estradiol-hexanoic acid derivative significantly increased the perfusion pressure and coronary resistance in comparison with the control conditions. Additionally, other data indicate that OTBDS-estradiol-hexanoic acid derivative increase left ventricular pressure in a dose-dependent manner (0.001 to 100 nM); nevertheless, this phenomenon was significantly inhibited only by nifedipine at a dose of 1 nM. These data suggest that positive inotropic activity induced by the OTBDS-estradiol-hexanoic acid derivative is via activation of L-type calcium channel. This phenomenon is a particularly interesting because the positive inotropic activity induced by this steroid derivative involves a molecular mechanism different in comparison with other positive inotropic drugs.

Activity exerted by a testosterone derivative on myocardial injury using an ischemia/reperfusion model.

Some reports indicate that several steroid derivatives have activity at cardiovascular level; nevertheless, there is scarce information about the activity exerted by the testosterone derivatives on cardiac injury caused by ischemia/reperfusion (I/R). Analyzing these data, in this study, a new testosterone derivative was synthetized with the objective of evaluating its effect on myocardial injury using an ischemia/reperfusion model. In addition, perfusion pressure and coronary resistance were evaluated in isolated rat hearts using the Langendorff technique. Additionally, molecular mechanism involved in the activity exerted by the testosterone derivative on perfusion pressure and coronary resistance was evaluated by measuring left ventricular pressure in the absence or presence of the following compounds: flutamide, prazosin, metoprolol, nifedipine, indomethacin, and PINANE TXA2. The results showed that the testosterone derivative significantly increases (P = 0.05) the perfusion pressure and coronary resistance in isolated heart. Other data indicate that the testosterone derivative increases left ventricular pressure in a dose-dependent manner (0.001-100 nM); however, this phenomenon was significantly inhibited (P = 0.06) by indomethacin and PINANE-TXA2 (P = 0.05) at a dose of 1 nM. In conclusion, these data suggest that testosterone derivative induces changes in the left ventricular pressure levels through thromboxane receptor activation.

New steroid derivative with hypoglycemic activity.

Data indicates that some steroid derivatives may induce changes on glucose levels; nevertheless, data are very confusing. Therefore, more pharmacological data are needed to characterize the activity induced by the steroid derivatives on glucose levels. The aim of this study was to synthesize a new steroid derivative for evaluate its hypoglycemic activity. The effects of steroid derivative on glucose concentration were evaluated in a diabetic animal model using glibenclamide and metformin as controls. In addition, the pregnenolone-dihydrotestosterone conjugate was bound to Tc-99m using radioimmunoassay methods, to evaluate the pharmacokinetics of the steroid derivative over time. The results showed that the pregnenolone-dihydrotestosterone conjugate induces changes on the glucose levels in similar form than glibenclamide. Other data showed that the biodistribution of Tc-99m-steroid derivativein brain was higher in comparison with spleen, stomach, intestine liver and kidney. In conclusion, the pregnenolone-dihydrotestosterone conjugate exerts hypoglycemic activity and this phenomenon could depend of its physicochemical properties which could be related to the degree of lipophilicity of the steroidderivative.