REACTION OF ORGANODILITHIUM REAGENT WITH α,α''''-DIHALO-o-XYLENE

ＲＥＡＣＴＩＯＮＯＦＯＲＧＡＮＯＤＩＬＩＴＨＩＵＭＲＥＡＧＥＮＴＷＩＴＨα，α'－ＤＩＨＡＬＯ－ｏ－ＸＹＬＥＮＥ￥ＨａｉＨｏｎｇＨＵＡＮＧ（ＩｎｓｔｉｔｕｔｅｏｆＭａｔｅｒｉａＭｅｄｉｃａ，ＣｈｉｎｅｓｅＡｃａｄｅｍｙｏｆＭｅｄｉｃａｌＳｃｉｅｎｃｅ?..     

PHARMACOLOGICAL STUDY OF AN IRREVERSIBLE PARTIAL AGONIST OF OPIATE RECEPTORS, A-α-CAO

A-α-CAO induces weak analgesia with very short duration in mice and is able to antagonize the analgesic effect of morphine (Mor) up to 3—4 days after a single injection. No tendency of dependence has been observed. It acts as a partial agonist on MVD with Ke value of 9×10~(-9) mol/L. Its antagonist effect remains after several washes and its agonist effect cannot be reversed by naloxone (Nx), provided the incubation time or the concentration of the agent is sufficient. On isolated GPI, A-α-CAO is a pure agonist with IC_(50) of 5.7×10~(-10) mol/L; this agonist effect cannot be removed by washing but can be reversed by Nx. On RVD and RbVD, it has antagonist effect against β-endorphine (β-end) and US0488H, which cannot be washed out easily, and the pA_2are 7.5 and 7.6 respectively. A-α-CAO also inhibits the specific binding of ~3H-etorphine (~3H-Etor) to the P_2 fraction of the mouse brain membrane with an IC_(30) of 3.2×10~(-9) mol/L. The inhibition on the high affinity binding sites of ~3H-Etor     

KINETICS AND MECHANISM OF PHOTOINDUCED POLYMERIZATION BY α,α-DIMETHOXY-α-PHENYL ACETOPHENONE

α,α-dimethoxy-α-Phenyl acetophenone (DMPA) is an efficient and thermally stable photoinitiator. Here its spectral characteristics in the transient state were shown. The transient species were identified as a benzoyl radical and a dimethoxyi benzyl radical that played a primary initiation role in polymerization. The kinetics and mechanism of the bulk polymerization of MMA were investigated. The exponent of DMPA concentration and k_p/k_1~(1/2) value were found to be 0.5 and 0.066 mol(-1/2)l~(1/2)s~(-1/2), respectively. The existence of oxygen led to obtain the polymer with higher molecular weight, which can be attributed to the occurrence of the subsequent polymerization induced by active polymer end group. In the photocrosslinking reaction, the dependence of DMPA content on initial rate has been found. A principal reason is that the sample contained higher percentage of DMPA has higher light-absorbed efficiency. In solid film, higher concentration of DMPA is permitted to be used because there is little excited state self-quenching effect in the rigid medium.     

STEREOCHEMISTRY OF THE BENZILIC ACID-TYPE REARRANGEMENT IN BASE-CATALYZED AUTOXIDATION OF 3α,5-CYCLO-5α-CHOLESTANE-6-ONE

The configuration of the hydroxy acid 2, a product from base-catalyzedautoxidation of 3α,5-cyclo-5α-cholestane-6-one,was established on the basis of NMRtechniques and the mechanism of the formation of 2 was discussed.     

UNUSUAL REACTION OF α,α-DIHALOGEN ETHERS WITH SULFINATE ANIONS

Abstract

Unsymmetrical dihalogen ethers halogenate arene sulfinate anions yielding the corresponding arene sulfonyl halides in addition to other products. A reaction mechanism is proposed.     

A MULTIGRAM PREPARATIVE SYNTHESIS OF CHOLEST-4-EN-3α,6β- AND -3α,6α-DIOLS

A preparative synthesis of cholest-4-en-3α,6β- and -3α,6α-diols 10 and 15 using cheap reagents and simple working-up procedures without chromatography on a multigram scale is described.     

CATALYTIC SYNTHESIS OF α-CYANO-α,β-UNSATURATED SULPHONES IN THE PRESENCE OF ORGANOTELLURIUM OXIDE

Using bis(p-methoxyphenyl)telluroxide(BMPTO)as the catalyst,phenylsulphonyl acetonitrile condensed easily with aromatic aldehydes atroom temperature to give -cyano- ,β-unsaturated sulphones in high yields.     

THE REARRANGEMENT OF 1,7β-DIMETHYL-7α-HYDROXY-8aα-CARBOXYMETHYL-9β-CARBOMETHOXY-4bα, 5, 6, 7, 8, 8a-HEXAttYDROFLUORENE LACTONE INDUCED BY DIBAL-H

1,7β- Dimethyl-7α- hydroxy-8aα-carboxymethyl-9β-carbomethoxy-4bα, 5, 6, 7, 8, 8α-hexahydrofluorene lactone(2) is converted to 8, 12-epoxyallogibberic acid methyl ester(4) by the action of diisobutyl aluminum hydride (DIBAL-H) with a novel rearrangement reaction.     

MAGNETOSTRATIGRAPHY OF PERMO-TRIASSIC BOUNDARY SECTION OF MEISHAN OF CHANGXING,ZHEJIANG

A hundred and eleven samples were collected from the Permian-Triassic boundarysection of Meishan (31.1°N, 119.7°E) which includes the Changxing Formation of thelate Permian and the Qinglong Formation of early Triassic. The thickness of the sectionis about 60 m. Paleomagnetic results indicate that six normal and reversed polarity zoneswere recorded in the section which all belong to the Illawarra mixed interval. Theboundary of Permo-Triassic lies at 1.2 m (or 2.7 m) above the bottom of normal polarityzone V. The magnetic minerals in the rocks of the lower part of the Changxing Forma-tion mainly are goethite, haematite and titaniferous magnetite while in the upper part ofthe formation are chiefly titanomagnetite and magnetite, goethite is secondary. Magne-tite and haematite as the main magnetic minerals were included in marl and mudstone ofthe Qinglong Formation. Based on the results of the magnetically stable samples thepaleopole position of 50.7°N, 230.3°E was obtained, meanwhile, the paleolatitude     

CRYSTAL AND MOLECULAR STRUCTURE OF O,O-DI-ISO-PROPYL-α-(1, 3, 4, 6-TETRA-O-ACETYL-2-DEOXY-β-D-GLU- COPYRANOSYL ) AMINO-α-p-METHYLPHENYLMETHYLPHOS-PHONATE

<正> The crystal C28H42O12NP is the monoclinic space group P21, with a = 10. 158(1), b=9. 069(1), c=18. 147(3) A , β=90. 72(1)% V=1671. 6 A3, Mr=615. 61, Z=2, Dx=1.23 g/cm3, μ=2.16 cm-1, F(000) = 660. The final R = 0. 071 and Rw = 0. 073 for 1860 observed reflections [I≥3σ(I)]. The results of structure analysis indicate that the configuration of the chiral carbon atom C(41) formed in the reaction is R *.     

Ab Initio Study of Prednisolone, 6α-Fluoroprednisolone, 9α-Fluoroprednisolone,and 6α,9α-Difluoroprednisolone

A theoretical study of prednisolone, 6-fluoroprednisolone, 9-fluoroprednisolone, and 6,9-difluoroprednisolone has been performed at the ab initio HF/6-31G, MP2/6-31G, and B3LYP/6-31G levels. Structural information and the electronic features of prednisolone and its derivatives and the synergistic effect of 6,9-difluoroprednisolone was examined. Contrary to the AM1 and MNDO results, we found 9-fluoroprednisolone is more stable than the 6-fluoroprednisolone. The increased corticosteroid activity of the 6,9-difluoroprednisolone is most likely due to electronic effects, mainly related to the receptor binding.     

ISOLATION AND IDENTIFICATION OF β-N-OXALO-L-α,β-DIAMINOPROPIONIC ACID AND ITS ISOMER α-N-OXALO-L-α,β-DIAMINOPROPIONIC ACID FROM PANAX SPECIES

The neuroexcitotoxic nonprotein amino acid β-N-oxalo-L-α, β-diaminopropionic acid (β-N-ODAP)and its isomer a-N-oxalo-L-α, β-diaminopropionic acid (α-N-ODAP)in Panax ginseng C. A. Meyer(cultivated ih Northeastern China), Panax quinquefolius L., Panax notoginseng F.H. Chen (cultivated in Southwestern China), Korean red ginseng and Jilin red ginseng were isolated and identified. Efficient separation and purification methods for β-N-ODAP and α-N-ODAP were developed.     

Synthesis of symmetrical acetylenic hydrocarbons and their α,ω-di-derivatives from α,α,α-trichloro- and α,α,α,ω-tetrachloro-alkanes

Summary By the action of sodium in xylene on polychloro hydrocarbons containing -CCl₂-CCl₂- or- CC1=CC1-, groupings the corresponding symmetrical acetylenic hydrocarbons containing 10,14, and 18 carbon atoms in the molecule were obtained. From ,-disubstituted tetrachloroalkanes by the same method 1,10-diethoxy-5-decyne, 1,14-diethoxy-7-tetradecyne, and 1,14-bisdiethylamino-7-tetradecyne were obtained.The spectra were determined in the Optical Laboratory of the Institute of Heteroorganic Compounds of the USSR by N. A. Chumaevskii, who we thank.     

A HIGHLY EFFICIENT SYNTHESTS OF (2E)-α,β-UNSATURATED AMIDES

Ａ　ＨＩＧＨＬＹ　ＥＦＦＩＣＩＥＮＴ　ＳＹＮＴＨＥＳＴＳ　ＯＦ　（２Ｅ）－α，β－ＵＮＳＡＴＵＲＡＴＥＤ　ＡＭＩＤＥＳ￥ＪｉｎＸｉｎｇＤＵ；ＸｉａｎＨＵＡＮＧ（ＤｅｐａｒｔｍｅｏｔｏｆＣｈｅｍｉｓｔｒｙ，ＺｈｅｊｉａｎｇＮｏｒｍａｌＵｎｉｖｅｒｓｉｔ...     

THE STEREOSELECTIVE SYNTHESIS OF N-ARYL-TRANS,TRANS-α-CARBOXYL-β-METHOXYCARBONYL-γ-ARYL-γ-BUTYROLACTAMS

Cis-1-methoxycarbonyl-2-aryl-6,6-dimethyl-5,7-diox-spiro-[2,5]-4,8-octadiones (1) in dimethyl ethylene glycol at room temperature react with anilines (2) to give N-aryl-trans,trans-α-carboxyl-β-methoxycarbonyl-γ-aryl-γ-butyrolactams (3) in good to excellent yields and high stereoselectivity.     

Conformation of α,α,α′-Trisubstituted Cyclododecanone

Ten α,α,α′-trisubstituted cyclododecanones were synthesized and characterized by elemental analyses, infrared, 1^H NMR and 13^C NMR spectra, and X-ray diffraction. NMR data could not give conformational information clearly, but some of their ring skeleton conformations of cyclododecanone moiety were showed to remain the unchanged [3333]-2-one conformation with little distortion, while the others were changed to the [3324]-2-one conformation in their crystal structures. These are consistent with the results of molecular mechanics calculation with Sybyl 6.9 software and Tripos force field, and semi-empirical quantum calculation with AM 1 method in Gaussian 98 software. Two geminal substituting groups are located at α-corner carbon atom, and the third group is at α-side-exo carbon atom in both conformations. Both [3333]-2-one and [3324]-2-one conformations are present in a dynamic equilibrium in the solution, but only one preferred conformation exists in the crystal solid.     

SYNTHESIS OF 5α-(17R,20R)-14,15-SECOCHOLESTANE

The synthesis of 5α-(17R,20R)-14,15-secocholestane fromcholesterol was reported.     

CALCULATIONS OF PHOTOELECTRON SPECTRA OF THE GROUP IV HALIDES BY SCF-X_α-SW METHOD

Photoelectron spectra of twenty-nine kinds of group IV halides which include CH_nX_(4-n) (n=0-3, X=F, Cl, Br,I), CFCl_3, CFBr_3,CClF_3, CF_2Cl_2,CF_2Br_2, SiF_4, GeF_4 and AX_4 (A =Si, Ge, Sn, X=Cl, Br) have been calculated by SCF-X_a-SW method and most of the calculations aro reported for the first time.The radius reduction factors have been defined and chosen carefully and the calculated results are in good quantitative agreement with experi-     

EFFECT OF N,N,N~'''',N~''''-TETRAALKYL TEREPHTHALAMIDE ON NON-ISOTHERMAL CRYSTALLIZATION KINETICS OF POLYPROPYLENE

The effect of N,N,N',N'-tetraalkyl terephthalamide (TATA) on the non-isothermal crystallization and melting characteristics of polypropylene (PP) was studied. The addition of TATA can lead to the formation of β-crystal PP. With the increase in TATA concentration the degree of crystallinity for β-crystal PP increased significantly, and that for α-crystal PP decreased, which indicated that TATA effectively induced the formation of β-crystal PP. WAXD also revealed the existence of β-crystal PP after the introduction of TATA into PP. PP containing TATA crystallized at a temperature range of 5-10℃ higher than that of pure PP, and the half-crystallization time (t1/2) and Avrami exponent (n) of PP at the same cooling rate were decreased by the addition of TATA, indicating that TATA influenced the crystallization rate and crystallization growth mode of PP. The rate constant of crystallization of PP containing TATA (Zc) was larger than that of pure PP, which further indicated that the crystallization of PP was accelerated by the addition of TATA.