1912-54-5Relevant academic research and scientific papers
3β-Acetoxy-6-nitrocholest-5-ene: Crystal structure, thermal, optical and dielectrical behavior
Shamsuzzaman,Mashrai, Ashraf,Khanam, Hena,Mabkhot, Yahia Nasser,Frey, Wolfgang
, p. 219 - 225 (2014)
3β-Acetoxy-6-nitrocholest-5-ene (2) has been synthesized from 3β-acetoxycholest-5-ene (1). We provided an analysis of the compound by means of FT-IR, FT-Raman, NMR and X-ray crystallography. In addition microstructural, thermal, optical and dielectrical properties were also investigated. The compound 2 crystallizes in the monoclinic space group P2 1 with cell dimensions, a = 15.7729 (13) A?, b = 9.8933 (8) A?, c = 17.8070(14) A?, α = 90.00, β = 96.176(4), γ = 90.00. The powder X-ray diffraction (PXRD) of the compound was recorded to ascertain phase homogeneity. The SEM micrograph showed the presence of brick shaped, elongated nitrocholestane particles with 177.12 × 25.53 × 5.69 μm dimensions. Thermogravimetric analysis showed stability of the compound up to 200 C. The dielectrical studies showed that with increase in frequency, the dielectric constant decreases and becomes almost constant at high frequencies.
Oxidation of cholesterol and O-protected derivatives by the environmental pollutant NO2?
Zalewski,Nathanael,White,Wille
, p. 4060 - 4063 (2016)
Exposure of O-protected and free cholesterol 1 to NO2· under exclusion of water leads to nitroimine nitrates 2 through a non-radical mechanism, which reveals the high susceptibility of the π system to oxidative damage. In the presence of moisture the reaction leads to 6-nitrocholesterols 3, which result from hydrolysis and oxidation of 2.
Synthesis of steroidal thiazolidinones as antibacterial agents based on the in vitro and quantum chemistry calculation
Khan, Salman A.,Asiri, Abdullah M.,Sharma, Kamlesh
, p. 1998 - 2004 (2013)
Steroidal thiazolidinone derivatives were prepared from the reaction of steroidal thiosemicarbazones with ethyl bromoacetate in dioxane. Steroidal thiosemicarbazones were prepared by reacting thiosemicarbazide with steroidal ketones. The structures of these compounds were elucidated by IR, 1HNMR, 13CNMR, and mass spectral study, and their purities were confirmed by elemental analyses. The antibacterial activities of these compounds were evaluated by the disk diffusion assay against two Gram-positive and two Gram-negative bacteria, and then the minimum inhibitory concentration of compounds were determined. The results showed that steroidal thiazolidinone derivatives are better in inhibiting growth as compared with steroidal thiosemicarbazone derivatives of both types of the bacteria. Compounds 7 and 8 are better antibacterial agents as compared with standard drug, Amoxicillin. Based on the quantum chemistry calculation at the DFT/6-31G*level, the frontier molecular orbitals and electrostatic potential of compounds 7 and 8 were also discussed.
Synthesis of spermidinylcholestanol and spermidinylcholesterol, squalamine analogues
Choucair, Bassima,Dherbomez, Michel,Roussakis, Cristos,El Kihel, La?la
, p. 11477 - 11486 (2004)
Several novel squalamine-related polyaminosterols are reported. The synthesis of 7α-N-[3N-(4-aminobutyl)aminopropyl]aminocholestanol I, 6α-N-[3N-(4-aminobutyl)aminopropyl]aminocholestanol II, 7α and 7β-N-[3N-(4-aminobutyl)aminopropyl]aminocholesterol (III and IV), was accomplished from cholesterol, they provide the first examples in which spermidine is introduced in the B steroidal ring. These molecules showed comparable antibacteria and fungi activities to squalamine, and were cytotoxic on a human non-small cell bronchopulmonary carcinoma line (NSCLC-N6). Therefore, these molecules with antibiotic and cytotoxic activities are promising for immune-compromised patients in cancer chemotherapy. Graphical Abstract.
Synthesis of 6(α,β)-aminocholestanols as ergosterol biosynthesis inhibitors
Beuchet, Pierre,El Kihel, Laila,Dherbornez, Michel,Charles, Georges,Letourneux, Yves
, p. 3627 - 3630 (1998)
Δ7-5-Desaturase catalyses one of the last steps in ergosterol biosynthesis in fungi. Moreover Δ5-unsaturation is necessary for the sparking function. Synthesis of three pairs of C-6 epimeric cholestanol derivatives are described as potential growth inhibitors. Preliminary results suggest that 6β-aminocholestanol is a potent antifungal agent.
Synthesis and in vitro antibacterial activity of novel steroidal (6R)-spiro-1,3,4-thiadiazoline derivatives
Khan, Salman A.,Asiri, Abdullah M.
, p. 1452 - 1457 (2012)
Novel steroidal (6R)-spiro-1,3,4-thiadiazoline derivatives were synthesized by the cyclization of steroidal thiosemicarbazones with acetic anhydride, screened in vitro against antibacterial activity using disc-diffusion method and the minimum inhibitory concentration. The results showed that steroidal thiadiazoline derivatives exhibited better antibacterial activity than the steroidal thiosemicarbazone derivatives. Chloro and acetoxy substituents on the 3β-position of the steroidal thiadiazoline ring increased the antibacterial activity. Among all the compounds, compound 7 and 8 were found better inhibitors of both types of bacteria (Gram-positive and Gram-negative) as compared to the respective drug amoxicillin. All the synthesized compounds were well characterized by spectroscopic methods such as IR, 1H-NMR, 13C-NMR mass, and elemental analysis and their stereochemistry was also discussed.
Synthesis and biological evaluation of some thiazolidinone derivatives of steroid as antibacterial agents
Khan, Salman Ahmad,Yusuf, Mohammed
, p. 2597 - 2600 (2009)
Steroidal thiazolidinone derivatives were prepared by the multi-step reactions of steroid. It is prepared from steroidal thiosemicarbazones with ethyl bromoacetate in dioxane. Steroidal thiosemicarbazones were prepared by the reaction of thiosemicarbazide with steroidal ketones. The structures of these compounds were elucidated by IR, 1H NMR, Fab mass spectrometries and their purities were confirmed by elemental analyses. The antibacterial activity of these compounds was evaluated by the disk diffusion assay against two Gram-positive and two Gram-negative bacteria and then the minimum inhibitory concentration (MIC) of compounds was determined. The results showed that steroidal thiazolidinone derivatives are better in inhibiting the growth as compared to steroidal thiosemicarbazone derivatives of both types of the bacteria (Gram-positive and Gram-negative). Compounds 7 and 8 are better antibacterial agents as compared to standard drug Amoxicillin.
Chemoselective epoxidation of cholesterol derivatives on a surface-designed molecularly imprinted Ru-porphyrin catalyst
Muratsugu, Satoshi,Baba, Hiroshi,Tanimoto, Tatsuya,Sawaguchi, Kana,Ikemoto, Satoru,Tasaki, Masahiro,Terao, Yosuke,Tada, Mizuki
, p. 5114 - 5117 (2018/05/26)
A new molecularly imprinted Ru-porphyrin complex catalyst on a SiO2 support was designed, prepared, and characterized in a step-by-step manner for the C5C6 epoxidation of cholesterol derivatives. High chemoselectivity for the C5C6 epoxidation of cholesterol derivatives without protecting the 3-position OH group and other oxidizable functional groups was achieved on the molecularly imprinted catalyst.
Synthesis and characterization of steroidal heterocyclic compounds, DNA condensation and molecular docking studies and their in vitro anticancer and acetylcholinesterase inhibition activities
Ali, Abad,Asif, Mohd,Khanam, Hena,Mashrai, Ashraf,Sherwani, Mohd Asif,Owais, Mohammad,Shamsuzzaman
, p. 75964 - 75984 (2015/09/28)
A facile, convenient and efficient approach for the synthesis of a new series of steroidal heterocyclic compounds (4-12) by reacting a mixture of compounds (1e-3e) with o-aminothiophenol/o-aminophenol/o-phenylenediamine is reported. The structural assignment of products is confirmed on the basis of IR, 1H NMR, 13C NMR, MS and analytical data. The compounds obey the Lipinski's 'Rule of Five' analysis based on computational prediction and pharmacokinetic properties. The anticancer activity has been tested in vitro against three cancer cell lines Hep3B (human hepatocellular carcinoma), MCF7 (human breast adenocarcinoma), HeLa (human cervical carcinoma) and one non-cancer normal cell i.e. PBMCs (peripheral blood mononuclear cell) by MTT assay. In addition, the synthesized compounds are also tested for their in vitro antioxidant activity by various reported methods in which compounds 10-12 exhibited good antioxidant activity. Nonenzymatic degradation of DNA has been investigated. The acetylcholinesterase (AChE) inhibitor activities of the steroidal derivatives are also evaluated using Ellman's method. Moreover, the application of compound 6 as a DNA gene transporter is evaluated by DNA condensation and ascertained by employing TEM and AFM, which illustrate that the compound 6 induces the condensation of CT-DNA. Molecular docking studies further characterize the interaction of the synthesized compounds with DNA. 2015
Bromination of Steroidal-6-ketoximes
Shafiullah,Ansari, Javed A.,Ansari, Shahid A.
, p. 271 - 272 (2007/10/02)
Bromation of 5α-cholestan-6-one oxime (1) with N-bromosuccinimide in carbon tetrachloride using benzoyl peroxide as a catalyst gave 6β-nitro-7α-bromocholest-4-ene (4), 7-bromocholesta-4,7-dien-6-one (5), 5α-cholestan-6-one (6) and 6-nitrocholest-5-ene (7). 3β-Chloro-5α-cholestan-6-one oxine (2) on similar treatment afforded 3β-chloro-5-bromo-5α-cholestan-6-one (8), 3β-chloro-5α,7-dibromocholest-7-en-6-one (9) and 3β-chloro-6-nitrocholest-5-ene (10).Under similar reaction conditions, 3β-acetoxy-5α-cholestan-6-one oxime (3) yielded 3β-acetoxy-5,7β-dibromo-5α-cholestan-6-one (11), 3β-acetoxy-7-bromocholesta-4,7-dien-6-one (12), 3β-acetoxy-6-nitrocholest-5-ene (13) and 3β-acetoxy-5α,7-dibromo-6β-nitrocholest-7-ene (14).The identity of the products has been established on the basis of their spectral data and comparison with authentic samples in known cases.
