A SIMPLE AND CONVENIENT ROUTE FOR PREPARATION OF OPTICALLY ACTIVE BICYCLOLACTONES

Optically active bicyclolactones 4 were prepared via a new simple route.     

A NEW CONVENIENT METHOD FOR THE SYNTHESIS OF PERFLUOROALKYL 2H-PYRROLE

The reaction between 2,5-Dimethylpyrrole (1) and R_FI (2)(R_F: a, Cl(CF_2)_4; b, Cl(CF_2)_6; c, Cl(CF_2)_8; d, n-C_6F_(13); e, n-C_8F_(17)) in the presence of Na_2S_2O_4-NaHCO_3 in acetonitrile resulted in the formation of 2-perfluoroalkyl-2,5-dimethyl-2H-pyrrole (3) as a major product in good yield.     

A NEW SYNTHETIC ROUTE TO α-ARYL PROPIONIC ACID AND A QUANTITA-TIVE STUDY OF THE PHOTO-S_(RN)1 REAC-TION OF ARYL HALIDES WITH CAN-BANION FROM ALKYL NITRILE

A new synthetic route leading to α-(2-(6-methoxynaphthy1))-propionic acid has ben developed. Successive one-step preparation of the appropriate α-aryl propionitrile from the aryl halides with propionitrile by photo-SRN1 procedure followed by hydrolysis gives the desired α-aryl propionic acid in excellent total yield. The photostimulated reaction of 2-bromonaph-thalene with acetonitrile or propionitrile in KNH2-NH3 solution to form the corresponding nucleophilic substitution product occurs with quantum yields considerably in excess of unit, while the pseudo-first-order rate constants of the photo-SRN1 are 30.9 and 47.0×10-5mol·s-1, respectively. Definite evidence to support the excitation of ground CTC and electron transfer from anion to ArX within the complex comes from the observation of the same φ>200 and φ>313 as well as MO calculation.     

STUDIES ON SEX PHEROMONE OF YELLOW RICE BORER, Scirpophaga incertulas (Walker), Pyralidae, Lepidoptera——IDENTIFICATION OF CHEMICAL STRUCTURE AND FIELD TRAPPING TESTS

The natural sex pheromone of the yellow rice borer, Scirpophaga incertulas is known to consist of 3 components: 16: Ald (Ⅰ), (Z)-9-16: Ald (Ⅱ) and (Z)-11-16: Ald (Ⅲ) by using single sex pheromone gland technique, high performance capillary CC, GC-MS, EAG, micro-chemical reaction as well as field trapping tests. Analysis of single sex pheromone gland showed that the precise ratio of the 3 components is 18.8 (Ⅰ): 27.1 (Ⅱ): 54.1 (Ⅲ) (％). The septura lure made according to the above precise blending showed strong attractancy in the field trapping tests. Maximun catch of a trap was 45 males/ day in the first generation in Guangxi Zhuang Autonomous Region. The average catch per day was 15.8 males.     

THE PARAMETER KERNELS FOR THE LINEAR INVERSION OF THE FREE OSCILLATION OF THE EARTH (Ⅰ)

In the linear inversion of the radial variation of the parameters of the Earth by usingthe observed frequencies of various normal modes of free oscillation of the earth, it is neces-sary to know the values of the kernels of the parameters ρ, μ and λ. This paper describesthe methods of the derivation of the formulas of these kernels. This is the first part of thepaper in which only the toroidal oscillations are considered. They are much simpler thanthose of the spheroidal ones, that we will consider in the second part of the paper. The data of the two types of oscillations are equally important in the solution of theinversion problem, and should be employed simultaneously, and we know that the toroidaloscillations are much simpler than the spheroidal ones, it seems wise to divide the whole programof the inversion problem into steps: first, by employing the toroidal data to correct the twoparameters ρ and μ in the mantle, then by using the spheroidal data to correct the remain-ing parameters, i.e. th     

THE PARAMETER KERNELS FOR THE LINEAR INVERSION OF THE FREE OSCILLATION OF THE EARTH (Ⅱ)

This is the second instalment of the paper, in which the method of derivation of the for-mulas of parameter kernels for the spheroidal oscillations are considered. The principle ofRayleigh is used to derive the formulas of the kernels of the two elastic parameters, i.e. μand λ. But for that of ρ, it is found very difficult to get satisfactory results. A new butsimpler approach is followed and very satisfactory results are obtained.     

STUDIES ON THE REACTION OF SULFUR,SELENIUM AND TELLURIUM WITH SODIUM HYDROXIDE UNDER PHASE TRANSFER CATALYSIS(Ⅱ).A CONVENIENT METHOD FOR THE SYNTHESIS OF BI(ACYL)DISULFIDES

A simple and general method for the synthesis of bi(acyl)disulfides isreported.Sulfur is allowed to react with sodium hydroxide to give sodium disulfideat 65℃ under PTC,which can react with acyl halides to afford bi(acyl)disulfides ingood to excellent isolated yields.The effects of solvents and phase transfercatalysts are discussed.     

STUDIES ON THE SYNTHESIS OF SESAMIN－GROUP LIGNANS V． A CONVENIENT METHOD FOR THE PREPARATION OF 2－ARYL－4－PHENYLOXAZOLES

ＳＴＵＤＩＥＳＯＮＴＨＥＳＹＮＴＨＥＳＩＳＯＦＳＥＳＡＭＩＮ－ＧＲＯＵＰＬＩＧＮＡＮＳＶ．ＡＣＯＮＶＥＮＩＥＮＴＭＥＴＨＯＤＦＯＲＴＨＥＰＲＥＰＡＲＡＴＩＯＮＯＦ２－ＡＲＹＬ－４－ＰＨＥＮＹＬＯＸＡＺＯＬＥＳ￥Ｃｏｒｒｅｓｐｏｎｄｅｎｔａｕｔｈｏｒ．２－ａｒｙｌ－４－ｐｈｅｎｙｌｏｘａｚｏｌｅｓ．Ｔｈｅｏｔｈｅｒｏｌｌｅｂｙｔｈｅｒｅａｃｔｉｏｎｏｆａ－ｍｅｔｈｙｌｐｈｅｎａｃｙｌｂｅｎｚｏａｔｅｗｉｔｈａｍｍｏｎｉｕｍａｃｅｔａｔｅｉｎｂｏｉｌｉｎｇａｃｅｔｉｃａｃｉｄｔｏｆｏｒｍａｆｕｔｕｒｅｏｆ２，４－ｄｉｐｈｅｎｙｌ－５ｍｅｔｈｙｌｏｘａｚｏｌｅａｎｄ２，４－ｄｉｐｈｅｎｙｌ－５－ｒｎｅｔｈｙｌｉｎｄｄａｚｏｌｅｂｏｔｈｉｎａｂｏｕｔ４０％ｙｉｅｌｄ，ｈｉｌｔｔｉｌｌｓｍｅｔｈｏｄｉｓａｐｐｌｉｃａｂｌｅｆｏｒｔｈｅｐｒｅｐａｒａｔｉｏｎｏｆ２－ａｒｙｌ－４－ｐｈｅｎｙｌｏｘａｚｏｌｅｓ．Ｂｙａｎａｌｏｇｙ，ｐｌｉｅｎａｃｙｌｂｅｎｚｏａｔｅｉｓａｌｌｏａｌｌｏｗｅｄｔｏｒｅａｃｔｗｉｔｈａｌｎｍｏｎｉｌｌｍａｃｅｔａｔｅｉｎｂｏｉｌｉｎｇａｃｅｔｉｃａｃｉｄ．Ａｍｉｘｔｕｒｅｏｆ２，４－ｄｉｐｈ     

A RHEOLOGICAL MODEL FOR THE PROCESS OF PREPARATION OF AN EARTHQUAKE

In this paper we try to explain the mechanical aspects of earthquake preparation process and pre-earthquake creep with the steady growth model of an in-plane shear (mode-Ⅱ) crack in rheologic materials. The fault creep which has occurred during the whole period of stable rupture propagation is the pre-earthquake creep. The result of our estimate shows that a considerable pre-earthquake creep had probably occurred before the Tangshan earthquake.     

THE SYNTHETIC ATTEMPT OF(±)-MALABARIC ACID AND(±)-ANISOMELOL——SYNTHE S IS OF PRECURSORS FOR(+)-MALABARIC ACID AND(±)-ANIOSMELOL

The precursors I(R′=CH_2OTHP,or CO_2Et)for(±)-Malabaric acid(1)and(±)-Anisomelol(2)were synthesized from geraniol 3 and homogeranyl iodide 5(2,6-dimetyl-9-iodo-2,6E-nonadiene)via Wadsworth-Emmons condensation and allylic regioselective chlorination.     

A NOVEL APPROACH FOR THE PREPARATION OF MEDIUM-SIZE LACTAMS

ＡＮＯＶＥＬＡＰＰＲＯＡＣＨＦＯＲＴＨＥＰＲＥＰＡＲＡＴＩＯＮＯＦＭＥＤＩＵＭ－ＳＩＺＥＬＡＣＴＡＭＳ￥ＹｕｎＸｉｎＢｏ；ＤｏｎｇＬｕＢＡＩ（ＳｈａｎｇｈａｉＩｎｓｔｉｔｕｔｅｏｆＭａｔｅｒｉａＭｅｄｉｃａ，ＣｈｉｎｅｓｅＡｃａｄｅｍｙｏｆＳｃｉｅｎ...     

A CONVENIENT SYNTHESIS OF 8-ALKYL S''''-ALKYL (ARYL) DITHIOPHOSPHORIC ACID DERIVATIVES**

The chlorination of S-alkyl(aryl) 0,0-dialkyl dithiophosphates with phosphorus oxychloride proceeds with isomerization to give S-alkyl S'-alkyl(aryl) dithiophosphorochtoridates, which react further with various nucleophiles in the presence of base to give the title compounds     

A CONVENIENT METHOD FOR SYNTHESIZING AND CHARACTERIZATION OF （Z）－ALKENOLS AND THEIR ACETATES

ＡＣＯＮＶＥＮＩＥＮＴＭＥＴＨＯＤＦＯＲＳＹＮＴＨＥＳＩＺＩＮＧＡＮＤＣＨＡＲＡＣＴＥＲＩＺＡＴＩＯＮＯＦ（Ｚ）－ＡＬＫＥＮＯＬＳＡＮＤＴＨＥＩＲＡＣＥＴＡＴＥＳ￥ＧｕＹＵＡＮ（ＤｅｐａｒｔｍｅｎｔｏｆＣｈｅｍｉｓｔｒｙ，ＰｅｋｉｎｇＵｎｉｖｅｒｓｉ...     

THE GROWTH OF SINGLE CRYSTAL AND THE DETERMINATION OF CRYSTALLOGRAPHIC PA RAMETERS OF (L-TRYPTOPHAN)~(A1)-INSULIN AND (D-TRYPTOPHAN)~(A1)-INSULIN

The crystal-growing conditions and the results of preliminary X-ray crystallographic analysis of (L-Try)~(A1)-insulin and (D-Try)~(A1)-insulin are reported. The single crystals of this pair of insulin analogue suitable for X-ray diffraction analysis have been grown in the citrate buffer system by still-setting method. They both belong to the trigonal system with space group R3. The parameters of the unit cell (L-Trp)~(A1)-insulin are αH= 80.31, cH= 37.45 and those of (D-Trp)~(A1)-insulin αH = 79.48, cH = 43.81. There are two molecules in an asymmetric unit. The obtained results are discussed.     

CN(R,S)METHOD FOR THE ASYMMETRIC SYNTHESIS OF ALKALOIDS

The alkaloids constitute a large groupof plant and animal substances in the struc-ture of Which the pyrrolidine and the pi-peridine rings are an integral feature.The     

THE PREPARATION AND CHARACTERISATION OF SALTS OF cis-BIS(2,2′-BIPYRIDINE)-CHLORO(DIMETHYLSULFOXIDE)-RUTHENIUM(II) AND THE CRYSTAL STRUCTURE OF THE PERCHLORATE DIHYDRATE. PRECURSORS FOR DNA-BINDING RUTHENIUM(II) COMPLEXES

Abstract

The preparation and characterisation of salts of the complex cation cis-bis(2,2′-bipyridine)-chloro(dimethylsulfoxide-S)ruthenium(IIII), [Ru(bpy)₂Cl(dmso)]⁺, is reported. The complex was prepared by the reaction of 2,2′-bipyridine with RuCl₃ · 3H₂O in dimethylsulfoxide. The value of this complex arises from its ability to react with suitable bidentate ligands particularly those that could act as DNA intercalators. The structure of [Ru(bpy)₂Cl(dmso)][ClO₄] · 2H₂O has been determined by single crystal X-ray diffraction. The complex crystallises in space group PI with a = 8.205(3), b = 10.448(4), c = 16.769(6) Å; α = 78.99(3)°, γ = 77.47(3)°, γ = 72.20(3)°, Z=2. The structure was refined by least-squares methods using 4070 observed reflections with 196 variable parameters (final R = 0.039).     

A STUDY ON THE RECONSTRUCTION OF THE EIGHTEENTH CENTURY MEIYU (PLUM RAINS) ACTIVITY OF LOWER CHANGJIANG(YANGTZE) REGION OF CHINA

This study presents a scheme for delimiting the meiyu period in the Lower Changjiang (Yangtze) region. This scheme was applied to the Clear and Rain Records of Nanjing, Suzhou and Hangzhou to reconstruct the 1723-1800 meiyu climate series. The beginning and ending dates, length, precipitation, and the intensity grades of meiyu were determined. The years of early, heavy, light, and empty meiyu were also given. Statistical analyses of the 18th century meiyu series indicate the existence of the quasi-periodicities of 2-3, 4-5, and 9 years. Many basic characteristics of the modern meiyu also existed in the 18th century. Some characteristics of the Northwest Pacific Subtropical High in the 18th century in typical meiyu years were inferred from the historical meiyu series.     

A NEW METHOD FOR THE AROMATIZATION OF 18-METHYL-ESTRA-4(5), 9(10)-DIEN-3,17-DIONE

An aromatization reaction was found when 18--methyl--estra--4(5),9(10)--dien--3, 17--dione(6) was treated with triethyl orthoforrnate in dioxane in thepresence of catalytic amount of p--toluenesulfonic acid (TsOH), and 18--methyl--9(11)--dehydroestrone--3--ethyl ether (8) was obtained in 70% yield. The mechanism wasfound to be a process of etherification--oxidation reaction.     

A NOVEL COUPLING REAGENT(PENTAFLUOROPHENYL DIPHENYLPHOSPHPATE)FOR THE PEPTIDE SYNTHESIS

Pentafluorophenyl diphenylphosphate was found to be a novelconvenient coupling reagent for the peptide synthesis with severaladvantages.Higher yield and lower racemization were found with thisreagent than DCCI.     

STUDIES OK TRANSFORMATION FOR ZEOLITE CRYSTAL(Ⅲ)——THE STABILITY OF ZEOLITE NaY AND THE STRUCTURE OF ZEOLITE NaPc

We investigated the crystallization of NaY and especially the transformation for NaY to NaPc type zeolite from an initial gel of the batch composition 3.3Na2O Al2O3 10SiO2 200H2O at 100℃and the changes of zeolite structures in the process of the transformation crystal using the modern techniques,A more detailed liquid phase transportation mechanism of the transformation was suggested.