93177-03-8Relevant articles and documents
Preparation and structural elucidation of the picolinyl ester of aldosterone for liquid chromatography-electrospray ionization tandem mass spectrometry
Yamashita, Kouwa,Tadokoro, Yumiko,Takahashi, Madoka,Numazawa, Mitsuteru
, p. 873 - 877 (2008)
Treatment of aldosterone with 35% HCl in EtOH or in MeOH followed by the picolinyl derivatization gave the picolinyl derivative of aldosterone-ethyl ether, 8, or methyl ether, 9, as a single and well-shaped liquid chromatographic peak. Picolinyl derivatization of aldosterone produced 21-picolinyl derivative of 18,20-anhydrohemiacetal derivatives, 6, with poor chromatographic peak with wide half-width. Further conversion of 6 to 8 required long reaction time (>4 h). Structure of each picolinyl or alkyl ether-picolinyl derivative, was carefully elucidated by nuclear magnetic resonance spectroscopy, electron ionization mass spectrometry and liquid chromatography-electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS). Enhancement of sensitivity (approximately 10-fold) in positive-LC-ESI-MS/MS of aldosterone was confirmed by the use of the alkyl etherpicolinyl derivatization when compared to the underivatized molecule.
18,21-ANHYDROALDOSTERONE AND DERIVATIVES
Harnik, M.,Kashman, Y.,Cojocaru, M.,Lewicka, S.,Vecsei, P.
, p. 11 - 20 (2007/10/02)
18,21-Anhydroaldosterone 8, 18,21-anhydro-19-noraldosterone 9, and 3α,5β-tetrahydro-18,21-anhydro-19-noraldosterone 13, which may be present in acid-processed urine, were prepared by cleaving their 20-ketal derivatives 2, 3, and 12 with hot mineral acid.Compounds 8 and 9 were also made by direct dehydration of aldosterone 5 and 19-noraldosterone 10 in good yield.The reverse ring opening of 8 to 5 could be carried out in moderate yield with an acetic acid-acetic anhydride-perchloric acid mixture, while an analogous ring opening of 9 gave only a poor yield of 10.