(a.) Turning, or causing to turn, toward the right hand; esp., turning the plane of polarization of luminous rays toward the right hand; as, dextrorotatory crystals, sugars, etc. Cf. Levorotatory.
Example Sentences:
(1) The dextrorotatory enantiomer of fluoxetine was slightly more potent than the levorotatory enantiomer in antagonizing the depletion of brain serotonin by p-chloroamphetamine in rats.
(2) The dextrorotatory morphinan opioid, dextrorphan, which has recently been reported to block the excitation of cortical neurons by N-methyl-D-aspartate, was found at 10-100 microM concentrations to attenuate both morphological and chemical evidence of glutamate neurotoxicity in murine neocortical cell cultures; a similar effect was found with its methyl ester derivative, dextromethorphan.
(3) The differences in antihypertensive activity of racemic and dextrorotatory propranolol cannot be explained by different plasma levels; the data indicate that the hypotensive effect of propranolol is due to beta receptor blockade.
(4) Subsequently, beta-End and levorphanol (10(-8) M), but not the dextrorotatory isomer, stimulated an elongation of the cells.
(5) It is dextrorotatory, [alpha](D) = +138 degrees , and has a pK(a) of 5.1.
(6) A compound, C14H24O2, which induces strong juvenilizing effects in the yellow mealworm, Tenebrio molitor L., following topical application to the pupal stage, was isolated in pure form from the roots of Echinacea angustifolia DC and tentatively identified as dextrorotatory (E)-10-hydroxy-4,10-dimethyl-4,11-dodecadien-2-one.
(7) In hypertensive patients, whose blood pressure was decreased by racemic propranololthe dextrorotatory isomer had no antihypertensive effect.
(8) The dextrorotatory enantiomer prevented the depletion of brain serotonin at any time after p-chloroamphetamine.
(9) The dextrorotatory enantiomer of aminoglutethimide is 38 times more potent than the levoenantiomer in inhibiting aromatization of testosterone by human placental microsomes.
(10) In a separate experiment, 100 micrograms of dextrorotatory and levorotatory gossypol was administered to male mice.
(11) The [3H]Tol2Gdn binding site displays stereoselectivity for dextrorotatory optical isomers of benzomorphan opiates known to have sigma-type behavioral effects.
(12) Fatty acids esterifying these fatty alcohols in M. marinum and M. ulcerans were found to belong to the phthioceranic series (dextrorotatory fatty acids), in contrast to those of the other species (laevorotatory fatty acids called mycocerosic acids), both groups having the same chain length and methyl-branched positions.
(13) The dextrorotatory gossypol, both in rat and mice, had less pronounced effect on the histoarchitecture of the testis in comparison to racemic and levorotatory gossypol.
(14) The non-narcotic dextrorotatory morphinan, dextrorphan, as well as its levorotatory opioid enantiomer, levorphanol, and its O-methyl derivative, dextromethorphan, have recently been shown to antagonize N-methyl-D-aspartate receptor-mediated neurotoxicity.
(15) Contrary to what is generally accepted, the dysphoric and psychotomimetic side effects of sigma opiates are mediated by the levo-and not by the dextrorotatory isomers.
(16) Increases in ventricular myocardial refractoriness and in QTc and paced QT intervals suggest that class III electrophysiologic actions contribute to the antiarrhythmic properties of dextrorotatory sotalol in this animal model.
(17) When dog urine was heated with acid rather than treated with beta-glucuronidase, the isolated p-HPPH contained a small preponderance of the dextrorotatory isomer, probably owing to production of d-p-HPPH from the dihydrodiol metabolite.
(18) The dextrorotatory and levorotatory isomers of chloroquine did not differ in their ability to stimulate the hydrolysis of tRNA by pancreatic ribonuclease A.
(19) The others were the dextrorotatory 2,6-bis-(3',4'-dihydroxyphenyl)-3,7-dioxabicyclo-[3,3,0]-octane 4,8-dione (dehydrodicaffeic acid dilactone) andits antipode.
(20) Another mu-agonist, levorphanol (20, 40, 80, or 160 micrograms) and dextrorphan (160 micrograms), its dextrorotatory isomer, were used next to evaluate opioid specificity.
Levorotatory
Definition:
(a.) Turning or rotating the plane of polarization towards the left; levogyrate, as levulose, left-handed quartz crystals, etc.
Example Sentences:
(1) In addition, the inhibitory activity of these acyclic analogues was enantioselective, exhibiting a preference, similar to the parent vesamicol, for the levorotatory isomer [(-)-11a vs (+)-11a].
(2) The levorotatory form of 5-hydroxytryptophan significantly improved the ataxia score.
(3) The stereochemistry of this material was established by conversion to levorotatory methyl 4-phthalimido [4(-2)H] butyrate.
(4) Extraction and fractionation of Frullania tamarisci has given, as the only allergenic component isolated, a levorotatory crystalline sutbstance, the structure of which is demonstrated.
(5) As several reports in literature confirmed the greatest antineoplastic activity of L-form in animals, the suggestion of further clinical investigation of levorotatory form as a separate preparation has been put forward.
(6) The dextrorotatory enantiomer of fluoxetine was slightly more potent than the levorotatory enantiomer in antagonizing the depletion of brain serotonin by p-chloroamphetamine in rats.
(7) The levorotatory compounds of R configuration showed stronger protective and also therapeutic effect in different experimental arrhythmias.
(8) These data indicate that the beta 2-receptor agonistic and anti-permeability actions of terbutaline are found solely in the levorotatory enantiomer.
(9) In five cases in which the levorotatory form of 5-hydroxytryptophan therapy was maintained for 12 months, the effect continued progressively.
(10) Some features of cerebellar ataxia have been reported to regress partially with long-term administration of 5-hydroxytryptophan or levorotatory form of 5-hydroxytryptophan.
(11) The racemic N-alkyl derivatives are more active than the racemic or even the levorotatory N-benzyl compound.
(12) By the consecutive oxidation and hydrolysis reactions a levorotatory intermediate was formed, presumably (-)-2-oxo-4-hydroxy-4-carbohydroxy-5-ureido-imidazoline.
(13) It was shown that the stereodifferentiation of anti-tumor effect of enantiomers was not outstanding although quite consistently in favour of levorotatory forms.
(14) A similar, but less potent neuron-protective effect, was seen with the opioid levorotatory enantiomer of DX, levorphanol (ED50, 40 microM).
(15) Treponemycin is a crystalline light-yellow compound with an mp of 93 to 95 degrees C, levorotatory, and soluble in most organic solvents.
(16) In this report, we identify that a major cortical receptor alteration in these disorders is a reduction in nicotinic receptors measured using both tritiated acetylcholine and levorotatory tritiated nicotine binding.
(17) The therapeutic index of the racemic 13 and its levorotatory enantiomer was about 1.7 times higher than that for ifosfamide and about 2.7 times higher than that for cyclophosphamide.
(18) In a separate experiment, 100 micrograms of dextrorotatory and levorotatory gossypol was administered to male mice.
(19) Among these compounds, the levorotatory 3-acetyl-N-(cyclopropylmethyl)morphinan (12) was found to be an orally active analgesic, comparable in potency to morphine (1), yet only weakly able to substitute for morphine (1) in morphine-dependent rats.
(20) The dextrorotatory gossypol, both in rat and mice, had less pronounced effect on the histoarchitecture of the testis in comparison to racemic and levorotatory gossypol.