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tachysterol
ta·chys·ter·ol T0008250 (tə-kĭs′tə-rôl′, -rōl′)n. An inactive compound, C28H44O, that is formed by irradiation of a precursor of vitamin D3 and can be converted back into that precursor.tachysterol
tachysterol[tə′kis·tə‚rȯl] (biochemistry) The precursor of calciferol in the irradiation of ergosterol; an isomer of ergosterol. tachysterol
tachysterol [tah-kis´ter-ol] an isomer of ergosterol, an antirachitic substance, produced by irradiation of ergosterol.ta·chys·ter·ol (tă-kis'tĕr-ōl), Sterol(s) formed by ultraviolet irradiation of any 5,7-diene-3β-sterol, which breaks the 9,10 bond, but usually from either or both of ergosterol and lumisterol to produce tachysterol2 (ertacalciol, (6E,22E)-9,10-secoergosta-5(10),6,8,22-tetraen-3β-ol) and from 7-dehydrocholesterol to produce tachysterol3 (tacalciol, (6E,3S)-9,10-secocholesta-5(10),6,8-trien-3β-ol). When reduced to the 5,7-diene (or 5,7,22-triene) form, dihydrotachysterol3 (10,19-dihydrocalciol) or dihydrotachysterol2 (10,19-dihydroercalciol), antirachitic action appears. This property has been of therapeutic interest, but tachysterol is being replaced by the true vitamin D hormone (calcitriol) and its derivatives.tachysterol (tə-kĭs′tə-rôl′, -rōl′)n. An isomer of ergosterol that forms vitamin D2 when irradiated with ultraviolet light.ta·chys·ter·ol (tak-is'tĕr-ol) Sterol(s) formed by ultraviolet irradiation of any 5,7-diene-3β-sterol. When it is reduced to the 5,7-diene (or 5,7,22-triene) form, antirachitic action appears. |