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171.
Shimoda K Kubota N Hirano H Matsumoto M Hamada H Hamada H 《Natural product communications》2012,7(4):529-530
Cultured plant cells of Marchantia polymorpha, Nicotiana tabacum, Phytolacca americana, Catharanthus roseus, and Gossypium hirsutum were examined for their ability to reduce curcumin. Only M. polymorpha cells converted curcumin into tetrahydrocurcumin in 90% yield in one day. Time-course experiment revealed a two-step formation of tetrahydrocurcumin via dihydrocurcumin. 相似文献
172.
Reaction of a series of (E)-3-phenyl-4-(p-substituted phenyl)-3-buten-2-ones with p-sulfamylphenyl hydrazine in glacial acetic acid gave the corresponding hydrazones, subsequent treatment of which with 30% HCl afforded pyrazole-1-sulphonamides. On the other hand, refluxing of chalcones with either thiosemicarbazide or isonicotinic acid hydrazide in ethanol containing a few drops of acetic acid gave pyrazoline-1-thiocarboxamides and isonicotinoyl pyrazolines, respectively. The structures of the synthesized compounds were determined on the basis of their elemental analyses and spectroscopic data. The antimicrobial activity of the newly isolated heterocyclic compounds was evaluated against Gram-positive, Gram-negative bacteria and fungi. Most of the compounds showed a moderate degree of potent antimicrobial activity. 相似文献
173.
Takuya Yokosaka Akinari Hamajima Tetsuhiro Nemoto Yasumasa Hamada 《Tetrahedron letters》2012,53(10):1245-1248
We developed a novel method for the asymmetric synthesis of highly functionalized γ-lactams through an organocatalytic aza-Michael–Michael reaction cascade using fumaric acid amide esters as multi-reactive substrates. Using chiral primary or secondary amine organocatalysts, we obtained two types of γ-lactams with three contiguous chiral centers in moderate to good yield with excellent enantioselectivity and diastereoselectivity. 相似文献
174.
A Lie hypersurface in the complex hyperbolic space is a homogeneous real hypersurface without focal submanifolds. The set of all Lie hypersurfaces in the complex hyperbolic space is bijective to a closed interval, which gives a deformation of homogeneous hypersurfaces from the ruled minimal one to the horosphere. In this paper, we study intrinsic geometry of Lie hypersurfaces, such as Ricci curvatures, scalar curvatures, and sectional curvatures. 相似文献
175.
Wafaa S. Hamama Hamada G. El‐Gohary Mamdouh Soliman Hanfi H. Zoorob 《Journal of heterocyclic chemistry》2012,49(3):543-554
This research work describes the synthesis and biological properties of some novel isolated or fused heterocyclic ring systems with pyrazole, for example; enaminones containing pyrazolone ring photochromic functional unit, 4‐[(4‐chlorophenylamino)methylene]‐3‐methyl‐1‐phenyl‐1H‐pyrazol‐5(4H)‐one (3) and some analogous derivatives 4, 9, and 10, also as pyrazolo[3,4‐b]pyridine, pyrazolo[3,4‐b]quinoline, pyrazolo[3′,4′:4,5]thieno[2,3‐c]pyrazoline and pyrazolo[3,4‐c]pyrazole were synthesized and characterized. Newly synthesized compounds were characterized by IR, 1H NMR, 13C NMR, mass spectral data and quantum mechanical calculations. Selected products were tested for their antibacterial and antitumor agents. 相似文献
176.
In this paper we consider extreme points and support points for compact subclasses of normalized biholomorphic mappings of the Euclidean unit ball Bn in Cn. We consider the class S0(Bn) of biholomorphic mappings on Bn which have parametric representation, i.e., they are the initial elements f (·, 0) of a Loewner chain f (z, t) = etz + ··· such that {e-tf (·, t)}t 0 is a normal family on Bn. We show that if f (·, 0) is an extreme point (respectively a support point) of S0(Bn), then e-tf (·, t) is an extreme point of S0(Bn) for t 0 (respectively a support point of S0(Bn) for t ∈[0, t0] and some t0 > 0). This is a generalization to the n-dimensional case of work due to Pell. Also, we prove analogous results for mappings which belong to S0(Bn) and which are bounded in the norm by a fixed constant. We relate the study of this class to reachable sets in control theory generalizing work of Roth. Finally we consider extreme points and support points for biholomorphic mappings of Bn generated by using extension operators that preserve Loewner chains. 相似文献
177.
178.
Yoshiaki Hamada Yoshiaki Amatatsu Masamichi Tsuboi 《Journal of Molecular Spectroscopy》1985,110(2):369-378
The infrared absorption spectrum of 1-aminopropene was observed for the first time in the gas phase. This molecule was produced by the thermal decomposition of cyclopropylamine. Two rotational isomers, cis and trans around the C=C double bond, occur. The relative yield of the conformers depends on the experimental conditions. The main conformer could not be identified experimentally, but an ab initio MO calculation suggests that the trans conformer is a little more stable form than the cis. These empirical assignments of the vibrational modes are supported by the ab initio MO calculation. 相似文献
179.
Interspecies differences in the pharmacokinetics of an antiallergic agent, 1-(2-ethoxyethyl)-2-(hexahydro-4-methyl-1,4-diazepin-1-yl)benzimid azole difumarate (KG-2413) after intravenous administration were investigated in rats, guinea pigs and dogs. The disappearance of unchanged KG-2413 base was described by biexponential curves in all three animal species. The areas under the plasma concentration-time curves (AUC) in rats, guinea pigs and dogs were 218, 421 and 369 ng.h/ml, respectively, at a dose of 2 mg/kg. The volume of distribution in rats was comparable to that in dogs, and was about three times greater than that in guinea pigs. This might be due to the difference in the unbound fractions of KG-2413 base in plasma (fu), that is, the values of fu in rats, dogs and guinea pigs were 0.607, 0.603 and 0.189, respectively. The first-order elimination rate constant from the central compartment (kcl) in dogs were smaller than those in rats and guinea pigs. Total body clearances (CLtot) of KG-2413 base in rats and guinea pigs were comparable to the hepatic blood flow rate (Q) of each animal. Assuming that KG-2413 base is only eliminated in the liver, relatively rapid metabolism of KG-2413 base occurred in the liver of rats and guinea pigs. In dogs, extrahepatic elimination was suggested because the value of CLtot seemed to be greater than that of Q. 相似文献
180.
The chelate metal complexes, such as tris(8-hydroxyquinolinate)aluminum (Alq3), have excellent electroluminescent (EL) properties. Several chelate metal complexes were developed and the experimental rule of molecular design for use in an organic EL device was found. When the chelate metal complex has the structure of an inner complex sell, the EL device is fabricated by conventional vacuum-vapor deposition. This rule was applied to some chelate metal complexes, and, as a result, various complex materials could be obtained. RGB (red, green, and blue) emission was achieved using only chelate metal complexes, after successfully obtaining high-luminance blue-emitting materials, such as azomethine-zinc complex. This shows that the chelate metal complexes can be applied to full-color flat displays as an emitting material. As for durability, when Bis(10-hydroxybenzo[h]quinolinato)beryllium (BeBq2) was used as an electron transport layer, a lifetime (initial luminance: 500 cd/m 2) of more than 3500 h, which is a practical level, was achieved in running tests. Thus, it seems that chelate metal complexes are a strong candidate as an organic EL material in practical use 相似文献