A new series of visible light-driven artificial rotary molecular motors is presented including the most red-shifted example to date.

Exploring routes to visible-light-driven rotary motors, the possibility of red-shifting the excitation wavelength of molecular motors by extension of the aromatic core is studied. Introducing a dibenzofluorenyl moiety in a standard molecular motor resulted in red-shifting of the absorption spectrum. UV/vis and 1H NMR spectroscopy showed that these motors could be isomerized with light of wavelengths up to 490 nm and that the structural modification did not impair the anticipated rotary behavior. Extension of the aromatic core is therefore a suitable strategy to apply in pursuit of visible-light-driven molecular motors.

A method for estimating urinary corticosteroid patterns is described. Normal 24-hour excretion values for tetrahydrocortisol (THF), allo-tetrahydrocortisol (allo-THF), tetrahydrocortisone (THE), cortisone (E), cortisol (F), tetrahydro-11-deoxycortisol (THS), tetrahydrocorticosterone (THB), allotetrahydrocorticosterone (allo-THB), tetrahydro-11-dehydrocorticosterone (THA), 11-dehydrocorticosterone (A), corticosterone (B) and aldosterone, as well as some calculated ratios are reported. The α-ketolic tetrahydrometabolites of cortisol include 25 per cent THF, 10 per cent allo-THF and 65 per cent THE. The mean THF/THE-ratio is 0.4, the mean F/E-ratio 0.8. The α-ketolic tetrahydrometabolites of corticosterone include 35 per cent THB, 35 per cent allo-THB and 30 per cent THA. The mean THB/THA-ratio is 1.2, the mean B/A-ratio 2.0. These figures seem to indicate that conversion of corticosterone to its 11-dehydrometabolites (B → A → THA) is less important than the corresponding metabolic pathway for cortisol (F →E →THE). Assuming that excretion reflects secretion, it is calculated that the adrenals secrete about 7 times as much cortisol as corticosterone and that about 1–3 per cent of the cortisol precursor Reichstein's S is secreted before 17-hydroxylation has been accomplished.

Urinary corticosteroid patterns were estimated before and after adrenocortical stimulation by exogenous corticotrophin (ACTH). The results indicate that changes in corticosteroid biosynthesis and metabolism depend on the duration of stimulation. Immediate effects are an increase in corticosterone production above that of cortisol (low F/B-ratio) and a shift in the metabolism of both cortisol and corticosterone in favour of all 11-hydroxycompounds. Late effects are characteristic of the patterns in Cushing's disease including a high F/B-ratio and low values for the 11-hydroxy-allocompounds (allotetrahydrocortisol and allotetrahydrocorticosterone). Changes in the ratios between cortisol, corticosterone and Reichstein's S as observed in Cushing's disease, adrenogenital syndrome and Addison's disease can be imitated by ACTH-induced acceleration of corticosteroid biosynthesis.