Studies on 16,17-Pyrazoline Substituted Heterosteroids as Anti-Alzheimer and Anti-Parkinsonian Agents Using LPS Induced Neuroinflammation Models of Mice and Rats.

Alzheimer's disease (AD) and Parkinson's disease (PD) are the most common forms of neurodegenerative disorders. Dehydroepiandrosterone (DHEA) has been reported as a neuroprotective steroid useful in the therapeutic management of neurodegenerative disorders such as AD and PD. Herein we report the synthesis and evaluation of a new series of 16,17-pyrazolinyl DHEA analogues 2-4a-d as neuroprotective agents using LPS-induced neuroinflammation animal models. Treatment with the pyrazoline substituted steroids considerably improved the LPS-induced learning, memory and movement deficits in animal models. Suppression of biochemical parameters of oxidative and nitrosative stress, acetylcholinesterase activity, and TNF-α levels was also observed. 16,17-Pyrazolinyl steroids 2c-4c substituted with a 4-pyridyl moiety at the 5-position of the heterocyclic ring were found to be the most potent agents and produced neuroprotective effects better than standard drugs celecoxib and dexamethasone. Of these pyrazoline substituted steroids, the N-acetyl analogue 3c displayed neuroprotective effects better than N-phenyl (4c), which in turn showed potency more than N-unsubstituted analogue 2c.

Synthesis and aromatase inhibitory activity of some new 16E-arylidenosteroids.

A new series of 16E-arylidene androstene derivatives has been synthesized and evaluated for aromatase inhibitory activity. The impact of various aryl substituents at 16 position of the steroid skeleton on aromatase inhibitory activity has been observed. The 16E-arylidenosteroids 6, 10 and 11 exhibited significant inhibition of the aromatase enzyme. 16-(4-Pyridylmethylene)-4-androstene-3,17-dione (6, IC(50): 5.2 µM) and 16-(benzo-[1,3]dioxol-5-ylmethylene)androsta-1,4-diene-3,17-dione (11, IC(50): 6.4 µM) were found to be approximately five times more potent in comparison to aminoglutethimide.

16α,17α-Ep-oxy-17ß-(1H-imidazol-1-yl)androst-4-en-3-one monohydrate.

In the title compound, C(22)H(28)N(2)O(2)·H(2)O, rings B and C adopt chair conformations. Ring A adopts an envelope conformation, with the non-fused C atom adjacent to the fused C atom bearing a methyl group as the flap atom. Ring D also adopts an envelope conformation, with the fused C atom not bearing a methyl group as the flap atom. The water mol-ecule links the mol-ecules via O-H⋯O and O-H⋯N hydrogen bonds, forming zigzag chains which run parallel to the c axis. Weak C-H⋯O inter-actions also occur.

Design, synthesis and evaluation of novel 16-imidazolyl substituted steroidal derivatives possessing potent diversified pharmacological properties.

As a part of our investigations into the structural-activity relationship studies of a novel class of medicinally active 16-substituted steroids, several new 16-imidazolyl substituted steroidal derivatives have been synthesized and pharmacologically evaluated in the current study. The new steroidal analogues 5, 6, 8, 9, 11 and 12 exhibited moderate cytotoxic effects in sixty cancer cell lines derived from nine cancers types. The imidazolyl substituted steroidal derivatives 6 (DPJ-RG-1241) and 7 (RB-401) were obtained as the powerful inhibitors of aromatase with IC50=0.18 µM and IC50=0.168 µM, respectively, approximately 1.2 and 1.4 times more potent in comparison to standard drug exemestane. The bis-quaternary steroids 13 and 14 displayed potent skeletal muscle relaxant properties. An affinity constant of 0.007 µM was observed for compound 14 on frog rectus abdominis muscle preparation and 13 displayed a very high anticholinesterase activity K(i)=25 nM, approximately 115-fold higher in comparison to standard drug galanthamine (K(i)=2.9 µM).

Synthesis and biological evaluation of 16E-arylidenosteroids as cytotoxic and anti-aromatase agents.

Taking into consideration the structural requirements for cytotoxicity and aromatase inhibition, several new 16E-arylidenosteroidal derivatives have been prepared and evaluated for their cytotoxic and aromatase inhibitory activity. The new steroidal analogues 3, 5-8 and 11 exhibited significant cytotoxic effects when screened against three cancer cell lines, MCF-7 (breast), NCl-H460 (lung) and SF-268 central nervous system (CNS) at 100 µM and sensible cytotoxic effects subsequently in sixty cancer cell lines derived from nine cancers types (leukemia, lung, colon, CNS, melanoma, ovarian, renal, prostate and breast cancers). The imidazolyl substituted steroidal derivatives 5 and 7 exhibited strong inhibition of the aromatase enzyme with 16-[4-{3-(imidazol-1-yl)propoxy}-3-methoxybenzylidene]-5-androstene-3ß,17ß-diol (7) displaying 13 times more potency in comparison to aminoglutethimide.