نتایج جستجو برای: dehydro aromatization
تعداد نتایج: 1931 فیلتر نتایج به سال:
Various tetrasubstituted pyrroles/pyrazoles have been prepared from nitro-substituted 1,3-enynes with aromatic amines/hydrazines via a copper-catalyzed cascade aza-Michael addition, cyclization and aromatization at room temperature. This protocol is also effective for the synthesis of tetrasubstituted pyrazoles in high yields.
In the stallion testis, aromatase activity was localized in the microsomal fraction. Androgen aromatization occurred through the loss of 1 beta,2 beta hydrogen atoms and appeared to involve free sulfhydryl groups. A single enzyme system seemed to aromatize androgen and norandrogen at the same rate while having a much lower affinity for norandrogens.
Incubation of (3S)-3-fluoro-3-deoxy-D-arabino-heptulosonate 7-phosphate with dehydroquinate (DHQ) synthase from three phylogenetically distinct sources resulted in the production of (6S)-6-fluoroDHQ and its epimer 1-epi-(6S)-6-fluoroDHQ. The differences in the product ratios of the reactions catalysed by each enzyme imply that 1-epi-(6S)-6-fluoroDHQ formation occurs by an unusual partial leakag...
The title compound, C(27)H(34)ClN, has been synthesized from 4-chloro-benzaldehyde and dehydro-abietylamine. There are two unique mol-ecules in the unit cell. Each mol-ecule has three chiral centres, which exhibit R, S and R absolute configurations. The two cyclo-hexane rings form a trans ring junction with classical chair and half-chair conformations.
The effectiveness of 13 N-acetylneuraminic acid derivatives as potential inducers of Arthrobacter sialophilus neuraminidase were examined. N-Acetylneuraminic acid nitrogen and thioglycosides were not inducers, whereas 2,3-dehydro-N-acetylneuraminic acid, a transition state analog for neuraminidases, was the most effective inductive ligand. The C-4 hydroxyl function of N-acetylneuraminic acid wa...
A novel one-pot synthesis of π-conjugated polycyclic compounds, which could undergo further facile transformation to form complex polycyclic heteroarene compounds, has been realized between 7-azaindoles and α,β-unsaturated ketones. This distinctive cascade process proceeds via a rhodium(iii)-catalyzed alkylation/copper-catalyzed radical annulation-aromatization pathway.
Two ways for the synthesis of binaphthyl were examined based on a chiral ligand-mediated asymmetric conjugate addition of 1-naphthyllithium to naththalene-2-carboxylic acid 2,6-di-t-butyl-4-methoxyphenyl esters. The one pot method by conjugate addition-elimination gave a relatively higher enantioselectivity than the two step synthesis based on addition and subsequent oxidative aromatization.
A versatile heterogeneous photocatalysis protocol was developed by using ruthenium bipyridyl tethered porous organosilica (Ru-POS). The versatility of the Ru-POS catalyst in organo-photocatalysis was explored by (i) oxidative aromatization of Hantzsch ester, (ii) reductive dehalogenation of alkyl halides, and (iii) functional group interconversion (FGI) of alcohols to alkyl halides.
The Grignard, Wittig, Tebbe, Horner-Emmons, and Reformatsky reactions of the 4-oxoproline esters gave the corresponding 4-alylated or 4-alkylidenated products, respectively. The products were properly treated with bases to cause aromatization, giving 4-substituted pyrrole-2-carboxylic acid esters such as methyl 4-methylpyrrole-2-carboxylate, which is a trail pheromone of Atta texana.
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید