Detail of "974-23-2"

Reference

A sensitive and selective HPLC/ESI-MS/MS assay for the simultaneous quantification of 16-dehydropregnenolone and its major metabolites in rabbit plasma

A sensitive and selective HPLC/ESI-MS/MS assay for the simultaneous quantification of 16-dehydropregnenolone and its major metabolites in rabbit plasma. Suryawanshi, Satyendra; Singh, S. K.; Gupta, R. C. (Pharmacokinetics and Metabolism Division, Central Drug Research Institute, Lucknow 226001, India). Journal of Chromatography, B: Analytical Technologies in the Biomedical and Life Sciences, 830(1), 54-63 (English) 2006 Elsevier B.V. CODEN: JCBAAI. ISSN: 1570-0232. DOCUMENT TYPE: Journal CA Section: 2 (Mammalian Hormones) A sensitive, selective and rapid liq. chromatog./electrospray ionization tandem mass spectrometric assay was developed and validated for the simultaneous quantification of 16-dehydropregnenolone (DHP) and its five metabolites 4,16-pregnadien-3, 20-dione (M1), 5-pregnene-3b-ol-20-one (M2), 5-pregnene-3b, 20-diol (M3), 5-pregnene-3b-ol-16, 17-epoxi-20-one (M4) and 5,16-pregnadien-3b, 11-diol-20-one (M5) in rabbit plasma using dexamethasone as internal std. (IS). The analytes were chromatographed on Spheri-5 RP-18 column (5 mm, 100 mm ′ 4.6 mm i.d.) coupled with guard column using acetonitrile:ammonium acetate buffer (, vol./vol.) as mobile phase at a flow rate of 0.65 mL/min. The quantitation of the analytes was carried out using API 4000 LC-MS-MS system in the multiple reaction monitoring (MRM) mode. The method was validated in terms of linearity, specificity, sensitivity, recovery, accuracy, precision (intra- and inter-assay variation), freeze-thaw, long-term, auto injector and dry residue stability. Linearity in plasma was obsd. over a concn. range of 1.56-400 ng/mL with a limit of detection (LOD) of 0.78 ng/mL for all analytes except M3 and M5 where linearity was over the 3.13-400 ng/mL with LOD of 1.56 ng/mL. The abs. recoveries from plasma were consistent and reproducible over the linearity range for all analytes. The intra- and inter-day accuracy and precision method were within the acceptable limits and the analytes were stable after three freeze-thaw cycles and their dry residues were stable at -60° for 15 days. The method was successfully applied to det. concns.Except for chemicals metioned above, 974-23-2 and 1096-38-4 are also used. of DHP and its putative metabolites in plasma during a pilot pharmacokinetic study in rabbits. .

Transformed steroids

80. Nucleophilic addition to isomeric steroidal arylazo olefins. Kamernitskii, A.Several substances are used for example 16597-57-2 and 974-23-2 which are their cas registry numbers. V.; Pavlova-Grishina, N. S.; Skorova, A. V. (Inst. Org. Khim. im. Zelinskogo, Moscow, USSR). Izv. Akad. Nauk SSSR, Ser. Khim., (6), 1353-7 (Russian) 1976. CODEN: IASKA6. DOCUMENT TYPE: Journal CA Section: 32 (Steroids) The azopregnadiene I (R = H) reacted wih HOAc via a 1,4-addn. reaction and subsequent acyl migration to give the hydrazone II, whereas addn. of HOAc to the C-16 epimer of I (R = Ac) gave the steroidal pyrazole III. Reaction of 3.beta.-hydroxy-16.alpha.,17-epoxy-pregn-5-en-20-one with 4-O2NC6H4NHNH2 in HOAc gave I (R = Ac), whereas 3.beta.-acetoxy-16.beta.,17-epoxy-17.alpha.-pregn-5-en-20-one and 4-O2NC6H4NHNH2 in HOAc-EtOH gave 16.beta.-I (R = Ac) and III. .