Some Doping Agents, Relations of Gas Phase Energetics, Thermal Properties and Biosynthesis

Year 1991, Volume: 7 Issue: 1-2, 39 - 48, 30.04.1991

Salih Cengiz

https://izlik.org/JA47UK65CA

Abstract

The most important characteristics of steroid hormones unlikc other hormones are that they are not storcd for subsequent secretion, but when required the steroid levels are controlled by the rate of
biosynthesis. The second important characteristics are related to the enzymes of the pathway, e.g. Il-HSD acts as hydrogenase or dehydrogenase depending on the organ which the enzyme works in it.
This study has been carried out to find the relationships between multistep fast biosynthesis and energetics of steroid molecules. Ionisation (1), Appearence potentials (A) and Activation energies (Ea) by using gas phase low energy electron impact ion source of VARIAN -MA 1'-112 Mass spectrometer to obtain I and A, and Shimadzu-DT-30 Thennal analyser to obtain thermal data. Results of energetics has
shown that the intermediates of biosynthesis are available for fast chain reactions. Furthennore some of the appearance potentials of the residues which were obtained by loosing the well known biologically
activc sites C-3 (-OH), C-3 (=0), C-IO (-CHJ), C-ll (-OIl), C-13 (-CH»), C-17 (-OIl), C-17 (=0) and C-21 (-CIl 20H) were found to be lower than ionisation potentials of the related whole molecules. These findings also confinn that steroids are unstable in the gas phase and but active under biological conditions.

Keywords

Steroids , Gas phase energetics , Mass spectrometry

References

• Gilman, kG., Goodman, L.S., Rall, T.W., Murad, F. (1985) in Goodman and Gilman's The
• Pharmacological Basis of Therapeutics, pp. 1481-1482, 7th edition, MacMillan Publishing Co., New York, toronto, London.
• Stachenko, J., Guraud, J.P. (1959) Endocrinology, 54, 730-738. Jones, T., Groom, M. and Griffiths, K. (1970) Biochem. Biophys. Res. Commun., 38, 355-367. Bell, J.l3.G., l3hatt, K., Hyatt, P.G., Tiat, J.F., Tiat, S.H.S. (1980) in Adrenal Androgens, Raven
• Press, New York.
• Hyatt, P.J., l3ell, J.l3.G., l3hatt, K.,Tiat, J.F. (1983) J. Endocrinol., 96, 1-5.
• Omura, T., Sato, R. (1964) 1. BioI. Chem., 239, 2370-2385.
• Klingenberg, M. (1958) Arch. Biochem. Biophys., 75, 376-385.
• Greiner, HI., Kramer, R.E., Rumbanah, R.C, Colby, H.R. (1977) Life Sci., 20, 1017-1026.
• Monder, C, Shackleton, CH.L. (1984) Steroids, 44,383-417.
• Howard, D.C, Eacho, I.P. (1985) 1. Steroid Biochem., 23, 477-482.
• Mayo, P.D, Reed, R.J. (1956) Chem.Ind., 41, 1481-1498.
• Budzikiewicz, H. (1972) in Biochemical Application of Mass Spectrometry, Chapter 10, J.Wiley &Sons, New York.
• Zaretsky, Z.W. (1976) in Mass Spectrometry of Steroids, J.Wiley &Sons, New York.
• Horowitz, lUI., Metzger, G.A. (1963) Anal. Chem., 35, 1464-1468.
• Rosenstock et aI., (1977) 1. Phys. Chem., Ref. Data Vol. 6., Supply I, Section l.
• Yalyill, F., Cengiz, S. (1986) Spektroskopi Derg., (Ozel SaYl), 130-138.