Fri Oct 27 Voet , Chapter 23, pp. Chapter 19, 691-696 . Pregnenolone is produced in adrenal glands and gonads.
Additional modifications give rise to the physiologically active steroid hormones.
Oxidation of C-3 to a keto group causes the double bond to shift into a conjugated position and gives the active C 21 hormone progesterone . A second pathway starts with a specific monooxygenase hydroxylation giving 17 -hydroxypregnenolone . A reverse aldol reaction eliminates acetaldehyde, to give the C 19 product dehydroepiandrosterone , which is oxidized to androstendione . Androstendione is reduced to hormonally active androgen, testosterone . Dihydrotestosterone is inactivated by conversion to androsterone among other inactive forms.