摘要:

AbstractThis paper deals with reactions involving an odd number of atoms. The bonds between the atoms alternatingly increase or decrease by one unit but one of the bonds remains unaffected. The reaction operator in terms of the formalism employed in the two previous papers thus is (+ ‐)nC in which C indicates the Constancy of the last mentioned bond.Many synthetically important processes belong to this class, among others acid‐ or base‐induced eliminations, ditto additions, isomerisations and substitutions, dipolar cycloadditions, fragmentations and tele‐re

ISSN:0165-0513    

DOI:10.1002/recl.19790980902

出版商:WILEY‐VCH Verlag    

年代:1979

数据来源: WILEY

摘要:

AbstractEthers (1 and 2) derived from dimethyl hydroxymalonate and 3‐methoxy‐1,3,5(10)estratrien‐17β‐ol or 17β‐hydroxy‐4‐androsten‐3‐one have been prepared. The cyclic ethylene acetal of 3‐methoxy‐1,3,5(10)‐estratrien‐17‐one (5) and of 3β‐benzyloxy‐5‐androsten‐17‐one (11) were converted stereoselectively into the corresponding 17β‐(2‐hydroxy‐ethyl) ethers 6 and 12 respectively by LiAlH4/AlCl3. Upon oxidation, esterification and treatment with lithium diisopropylamide/methyl chloroformate the 17‐bis(methoxycarbonyl)methyl esters 1 and 15 were obtained. Catalytic h

ISSN:0165-0513    

DOI:10.1002/recl.19790980903

出版商:WILEY‐VCH Verlag    

年代:1979

数据来源: WILEY

摘要:

AbstractQuenching the enolates of cyclic β‐diketones or 2‐oxocycloalkanecarboxylates with phenylsulfenyl chloride or methylsulfenyl chloride produces the correspondingx‐sulfenylated products. Nucleophilic attack on thesex‐sulfenylated 1,3‐dicarbonyl compounds produces regiospecific sulfenylated linear dicarboxylic acids, acid esters, diesters or oxo esters suitable for further chemical transformation, this has been demonstrated in the synthesis of the queen substance of the honoy bee. In some cases recyclization of the intermediate enolates was observed to regiospecific sulfenylated cycl

ISSN:0165-0513    

DOI:10.1002/recl.19790980904

出版商:WILEY‐VCH Verlag    

年代:1979

数据来源: WILEY

摘要:

AbstractBr2Au(Bu2dtc) forms solid compounds withtrans‐stilbene,trans‐azobenzene,trans,trans‐1,4‐diphenyl‐1,3‐butadiene, tolane and dibenzyl, of formula [Br2Au(Bu2dtc)]2·organic component. The crystal structures of the title compounds are solved. No specific interactions between the dithiocarbamato compound and the organic component

ISSN:0165-0513    

DOI:10.1002/recl.19790980905

出版商:WILEY‐VCH Verlag    

年代:1979

数据来源: WILEY

摘要:

AbstractDienamines derived from 8a‐methyl‐1,6‐dioxo‐1,2,3,4,6,7,8,8a‐octahydronaphthalene (2) and ( + )(7aS)‐7a‐methyl‐2,3,5,6,7,8‐hexahydro‐1,5(1H)‐indandione (12) react with 3‐bromo‐2‐(3‐methoxyphenyl)propene (3) to give the corresponding 5‐ and 4‐substituted alkylation products 8 and14a, respectively. 8 can be directly cyclized to 6‐methyl‐D‐homoequilenin derivative 9 by heating with acid. While14acan be similarly converted into the corresponding equilenin methyl ether (15a), better yields in the cyclization step are achieved by initial reduction of the 5‐ring ketone function and acetylation of the resulting alcohol. The latter sequence of reactions with14a, derived from 12, gives optically active 17β‐acetoxy‐6‐methylestra‐1,3,5,7,9,14‐haxaen‐3‐ol methyl ether (15b), which can serve

ISSN:0165-0513    

DOI:10.1002/recl.19790980906

出版商:WILEY‐VCH Verlag    

年代:1979

数据来源: WILEY

摘要:

AbstractThe synthesis and complex formation of a new hexadentate, nitrogen‐donor ligand are described. The ligand N,N,N′,N′‐tetrakis(2‐benzimidazolylmethyl)‐1,2‐ethanediamine (EDTB) is prepared by condensation of 1,2‐benzenediamine and ethylenediaminetetraacetic acid. This chelate ligand appears to be able to solvate first‐row transition‐metal ions in an octahedral manner, resulting in species M(EDTB) (anion)2and M2(EDTB) (anion)4. The products have been analysed and characterised by spectroscopic and magnetic techniques (EPR, NMR, ligand‐field and IR).During recent years much interest has arosen in the bioinorganic chemistry of first‐row transition‐metal ions, in particular with respect to the relationships between the activity and structural properties of metalloproteins, such as hemocyanin, tyrosinase, laccase, cytochrome‐c‐oxidase, superoxide dismutase and carbonic anhydrase.1–3Nitrogen‐donor ligands such as imidazoles of polypeptidyl histidines have been shown to play an important rǒle in the coordination of the metal ions in such proteins.4,5Furthermore, the stereochemistry imposed by the rigid structure of the protein seems to be responsible for some of the characteristic properties an

ISSN:0165-0513    

DOI:10.1002/recl.19790980907

出版商:WILEY‐VCH Verlag    

年代:1979

数据来源: WILEY

ISSN:0165-0513    

DOI:10.1002/recl.19790980901

出版商:WILEY‐VCH Verlag    

年代:1979

数据来源: WILEY