Preparation and characterization of mixed hydroxy-Fe-Al pillared montmorillonite with large basal spacing

Mixed hydroxy-Al-Fe pillared montmorillonites with large basal spacing were successfully prepared through cation-exchanging of Na +- montmorillonite with mixed hydroxy-Al and hydroxy-Fe pillaring solutions made from hydrolysis of corresponding metal salts, followed by calcination to convert hydroxy-Al and hydroxy-Fe into intercalated polycations. According to XRD analysis, the basal spacing d(001) of pillared products dramatically enlarged from 12.7 *! in the Na-montmorillonite to 81 *! in the hydroxy-Fe -montmorillonite and 77.5 *! in mixed hydroxy-Al-Fe-montmorillonite. The N_2 BET surface areas of the pillared montmorillonites also greatly increased to more than 200 m 2/g as compared to about 27 m 2/g for the Na-montmorillonite. IR analysis of hydroxy-Fe, and mixed hydroxy-Al-Fe pillared montmorillonites revealed a new absorption vibration at 1384 cm -1 wavelength. XRF elemental analysis data also showed a high content of Fe_2O_3 in the hydroxy-Fe pillared montmorillonite.

SELECTIVE REDUCTION OF 3,17—DIOXO—STEROIDS TO 17β-HYDROXY-3-OXO-STEROIDS

11β-Hydroxy-androst-4-en-3,17-dione(1a),androst-4,9(11)-dien-3,17- dione-(2a),androst-4-en-3,11,17-trione(3a),11α-methoxy-androst-4-en-3,17-dione (4a)and 11β-metboxy-androst-4-en-3,17-dione(Sa)were selectively reduced to the corresponding 17β-OH derivatives in one step without the protection of 3- oxo(and 11-oxo,in the case of 3a)group with the yields ranging from 65% to 79%.In these reactions,the ditute NaBH_4(or KBH_4)solution in methanol was added dropwise to the 3,17-dioxo-steroids solution in methanol-benzene-pyridine, while the reaction mixtures were well stirred at -5～5℃.Acid(such as gtacial acetic acid)was added to quench the reactions.The resulted testosterone derivatives(1b～5b)were purified by flash chromatography. This method appties to the reduction of other 3,17-dioxo-steroids such as△~1 -3-one,△^(1.4)-3-one,△^(4.6)-3-one,△^(1.4.6)-3-one containing compounds.

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.

SYNTHESIS OF(4S,5R)-5-HYDROXY-4-DECANOLIDE.THE PROPOSED AUTOREGULATOR FROM STREPTOMYCES

(4S,5R)-5-Hydroxy-4-decanolide ,the proposed autoregulator from streptomyces Griseus was synthesized from an allyl alcohol 2,employ- ing the Sharpless kinetic resolution and the reaction of diethyl malonate with the epoxy compound as two key steps.

Synthesis and Crystal Structure of Tris(N-p-methylphenyl-3-hydroxy-2-ethyl-4-pyridinonato)iron(III)

The complex [Fe(C14H14NO2)3]2H2O has been prepared by reaction of N-p-methylphenyl-3-hydroxy-2-ethyl-4-pyridinone with FeCl36H2O. A single-crystal X-ray study shows that the iron atoms lie in a trigonally distorted octahedral environment coordinated to the hydroxy and ketone oxygen atoms of three ligands in the mer configuration Mr=773.57(C42H46N3O8Fe). The crystal is hexagonal with space group P31c; a=15.943(2), c=17.612(4)? V=3877.0(12)?, Z=4, Dc=1.325g/cm3, m=0.445mm-1, F(000)=1634, R=0.0446, wR= 0.1154 for 3085 reflections with I >2s(I). The bond lengths from iron to oxygens are 1.980(1)?for the ketone oxygens and 2.071(1)?for the hydroxy oxygens. The molecule exhibits the expected propeller shape, and the angle of the trigonal twist is 48.37. The dihedral angles are 0.5(2)?between chelate ring plane and pyridine ring plane and 71.31(7)?between pyridine ring plane and benzene ring plane. The solvent H2O(O(3) and O(4)) molecules are linked with O(2) and O(1) by hydrogen bonds with bond lengths 2.900(1) and 2.999(1)? respectively.

Determination of Trace Silver( Ⅰ ) in Basic Aqueous Solution by Electrochemiluminescence of a New Reagent 6-(2-Hydroxy-4-Diethylaminophenylazo)-2,3-Dihydro-1,4-Phthalazine-1,4-Dione

The electrochemiluminescence (ECL) of a new reagent 6- (2-hydroxy- 4 diethy laminophenylazo)-2,3-dihydro-1 ,4-phthalazine-1,4-dione (HDEA) in a basic aqueous so lution was studied by using the apparatus designed by ourselves. Trace amounts of silver ( Ⅰ ) shows a significant effect on the efficiency of light emission of HDEA during a positive trigonometrical wave pulse was exerted on the solution. The linear relationship between the light intensity and the concentration of silver( Ⅰ ) occurs in the range of 5. 0×10-8 to 3. 0×10-8 mol/L Ag(Ⅰ ) in a medium of KOH-KCl-HDEA (pH= 12. 8). The detection limit of the method is 2. 0×10-8 mol/LAg( Ⅰ ), and the r. s. d. for 1.0×10-7 mo)/L Ag ( Ⅰ ) is 5%. Of 21 metal ions concerned, only nickel( Ⅱ ), cerium( Ⅳ ) and cobalt( Ⅱ ) interfere the silver detection seriously; Ⅰ and Br also have some interference.

Synthesis and Characterization of Some Transition Metal Chelates of 5-(1-Hydroxy-6-Naphthylazo-3-Sodium Sulphonate) Thiobarbituric (L_1) and Barbituric (L_2) Acids

Some transition metal chelates of two ligands L1 and L2 were prepared and characterized by elemental analysis. The IR and 1H NMR spectra of several chelates of two ligands L1 and L2 showed the involvement of the azo group in chelation with the transition metaI ions, in most of the studied chelates, and that the two ligands L1 and L2 showed the involvement of the azo group in chelation with the transition metal ions, in most of the studied chelates, and that the two ligands L1 and L2 were coordinated either in the enol or the keto form. IR spetra also showed that Fe(III)-, Ni(II)-, Mn(II)-, VO(II)-L1 and Cu(II)-L2 chelates behaved in a bidentate manner, in contrast with the two (1:1) M:L cobalt chelates with the two ligands are tridentate.TG analysis indicated the presence of three to twelve water molecules of hydration eliminated on heating up to 150℃ and one or two coordinated water molecules removed at 150~180℃.The octahedral structure is proposed fOr all the chelates, except Cu(II)-L2 and Ni(II)-L1 chelates which have square planar geometry, based on their electronic spectra

SYNTHESIS AND CHARACTERIZATION OF 2-(2-HYDROXY-3,5-DINITROPHENYLAZO)-7-(4-CHLORO-PHOSPHONPHENYLAZO)-1, 8-DIHYDROXY-NAPHTHALENE-3, 6-DISULF-ONIC ACID (CPAP) AS NEW REAGENT FOR DETERMINATION OF TOTAL PARE EARTHS

This paper reports the synthesis and general properties of the new reagent CPFP. Its dissociation constants have been determined. The characterization in determinating total RE with CPAP reagent has been investigated in detail. Analytic data for synthetic sample are satisfactory.

First Synthesis of (±)-3-(5-Hyd roxy-4-Methyl-7-Isopropyl-3E,7-Octadienyl)- △~2-Butenolide

An efficIent total synthesis of (±)-3-(5-hydroxy-4-methyl-7 △-butenolide, a new fi1n1esane-b;.Fed homosesquiterPeIle lactone. starting from geraniol through eightsteps are described.

The enantioselective synthesis of(4S,5S)-and(4S,5R)-5-hydroxy-4-decanolide,the autoregulators from Strepotomyces griseus

(4S,5S)-and(4S,5R)-5-Hydroxy-4-decanolide(1a and 1b),the proposed autoregula- tors from Strepotomyces Griseus were synthesized from a propargyl alcohol 2 in an overall yield of 30%,employing the Sharpless asymmetric epoxidation as the key step.

Quinoline alkaloids isolated from Scolopendra subspinipes mutilans

Objective: To study the quinoline alkaloids from the ethanol extract of Scolopendra subspinipes mutilans(SSM).Methods: The chemical constituents were isolated and purified by macroporous resin column, medium pressure preparation chromatography, and semi-preparative HPLC. Their structures were elucidated by IR,MS, and NMR experiments.Results: Three quinolone alkaloids were obtained and identified as 3-hydroxy-4-methoxyquinolin-8-yl hydrogen sulfate(1), jineol-8-sulfate(2), and jineol(3), respectively.Conclusion: Compound 1 is a new compound from SSM.

An Improved Method for the Sy nthesis of Optically Active Tomoxetines and Fluoxetines

A chemoenzymatic approach was applied to the preparation of chiral 3-hydroxy-3-arylpropionates and 3-hydroxy-4,4,4-trifluorobutanoate that are potential precursors for certain chiral pharmaceuticals including chiral tomoxetines and fluoxetines.