The synthesis of the diastereoisomeric lactones 12a and 12b as models for the carboxylate binding pocket of vancomycin is described; the structure of 12a, which corresponds to the diphenyl ether rotamer found in vancomycin, is established by X-ray crystallographic analysis.

A series of monobactam analogues lacking 3-acylamino side chains has been synthesised from the photoisomer of 4-methyl-2-pyridone; none of these analogues showed any useful biological activity.

AbstractAus dem Penemcarbonester‐Derivat (Ia) erhält man die Substitutionsprodukte (Ib) und (Ic), die zum Lacton (II) cyclisiert werden können.

Chemischer InformationsdienstVolume 9, Issue 13 Isocyclic Compounds ChemInform Abstract: STEROID ANALOGS. PART 1. PREPARATION OF INTERMEDIATES CONTAINING RINGS C AND D D. J. HUMPHREYS, D. J. HUMPHREYSSearch for more papers by this authorC. E. NEWALL, C. E. NEWALLSearch for more papers by this authorH. A. PASKINS, H. A. PASKINSSearch for more papers by this authorG. H. PHILLIPPS, G. H. PHILLIPPSSearch for more papers by this author D. J. HUMPHREYS, D. J. HUMPHREYSSearch for more papers by this authorC. E. NEWALL, C. E. NEWALLSearch for more papers by this authorH. A. PASKINS, H. A. PASKINSSearch for more papers by this authorG. H. PHILLIPPS, G. H. PHILLIPPSSearch for more papers by this author First published: March 28, 1978 https://doi.org/10.1002/chin.197813163Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume9, Issue13March 28, 1978 RelatedInformation

AbstractUnter der Einwirkung von Tageslicht reagieren die Li‐Salze der Nitrocyclohexane (I) mit dem Dinitrocyclohexanol unter Bildung von 1,1 ′‐Dinitro‐bicyclohexylen; diese Dinitrobicyclohexyle werden, ebenfalls unter Lichteinwirkung, durch Na,S zu den Bicyclohexylidenen (III) reduziert.

(±)-7β-Hydroxy-6β-methyl-trans-bicyclo[4.3.0]nonan-3-one (6) and (±)-rel-(1R,6R,7R)-7-[(1R)-1-hydroxyethyl]-6-methylbicyclo[4.3.0]nonan-3-one (10), key intermediates for the synthesis of 6,7-dinor-5,8-secoestr-9-enes, were prepared from (±)-6-methyl-trans-bicyclo[4.3.0]nonane-3,7-dione (4). Reduction of (4) with a modified Henbest reagent (hexachloroiridic acid–trimethyl phosphite–triethylamine–aqueous propan-2-ol) gave (±)-3α-hydroxy-6β-methyl-trans-bicyclo[4.3.0]nonan-7-one (13) as the major product; with Lalancette's reagent (sulphurated sodium borohydride) the (±)-3β-hydroxy-epimer (15) was formed. Surprisingly, reduction of (±)-6-methyl-cis-bicyclo[4.3.0]nonane-3,7-dione (19) with either the Henbest or the Lalancette reagent gave (±)-3α-hydroxy-6β-methyl-cis-bicyclo[4.3.0]nonan-7-one (20).

AbstractDie Behandlung von (I) mit Triethylamin ergibt das Ringspaltungsprodukt (II), das beim Erhitzen zum Isomeren (III) cyclisiert und mit Triethylamin wieder in (II) übergeht.

The condensation of cycloalkanones with cycloalkanecarboxylic acids has been shown to be a general method for the preparation of cycloalkylidenecycloalkanes bearing different functional groups in the two halves of the molecule.Condensation of bicyclic hydroxy-ketones representing rings C and D of the steroid nucleus with the dilithium salts of 4-substituted cyclohexanecarboxylic acids (representing ring A) gave β-hydroxy-acids, which were trans-formed by lactonisation and subsequent pyrolysis into 3-substituted Δ9-6,7-dinor-5,8-seco-estrenes and -pregnenes. The stereochemistry of these compounds has been elucidated by n.m.r. spectroscopy using a lanthanoid shift reagent, and by reference to conformation theory and the Woodward–Hoffmann rules.In order to provide model routes to 11-hydroxy-analogues of these compounds, 2-hydroxy-1,1′-bi(cyclohexylidene)(46) was prepared from 1-(cyclohex-1-enyl)cyclohexanecarbonitrile (38) by epoxidation and reduction with lithium–ammonia, and from 1-(cyclohex-1-enyl)cyclohexanecarboxylic acid (40) by epoxidation, chromatography over silica gel, and pyrolysis of the resulting γ-hydroxy-β-lactone. Similar treatment of βγ-unsaturated acids derived from the seco-steroidal β-hydroxy-acids mentioned above gave none of the desired 3-substituted 11α-hydroxy-Δ9-6,7-dinor-5,8-seco-steroids.

AbstractDas aus dem Keton (I) zugängliche symm. Azin (II) cyclisiert mit H25 in Aceton/CHZCI, zu einem 4:9: 12‐Gemisch aus den Thiadiazolidinen (III).

AbstractDas geschützte Hydroxybicycloketon (Ib) ‐ erhalten aus (Ia) ‐ wird mit dem Carbonsäure‐di‐Li‐Derivat (II) zu der Hydroxysäure (i)‐(IIIa) kondensiert, deren Lacton (i)‐(IVa) (Diastereoisomerengemisch) bei der Pyrolyse den Ether (i)‐(V a) (Diastereoisomerengemisch) und den Alkohol (i)‐(Vb) gibt; durch saure Hydrolyse erhält man aus dem Gemisch ausschließlich das Di‐nor‐secoöstrenol (i)‐(Vb).

A general synthesis of symmetrical bi(cycloalkylidene)s is reported, involving successive reaction of an azine with hydrogen sulphide to give a 1,3,4-thiadiazolidine, oxidation to a Δ3-1,3,4-thiadiazoline, pyrolysis to a thiiran, and desulphurisation. The stereochemistry of the products and intermediates was elucidated by 1H n.m.r. spectroscopy with reference to the Woodward–Hoffmann rules and to conformation theory. The intermediate thiadiazolidines may also be prepared by direct condensation of a cycloalkanone with hydrazine and hydrogen sulphide, with different stereochemical consequences.A novel synthesis of mixed azines by oxidation of carboxyhydrazones with lead dioxide is described. Combined with the above process, this constitutes a general synthesis of unsymmetrical bicycloalkylidenes. This method has been used to prepare 3,17-disubstituted Δ9-6,7-dinor-5,8-secoestrenes. The stereochemistry at C-3 in these olefins and in the intermediate episulphides was assigned by correlation with known compounds, and the orientation of the sulphur atom in the episulphides was elucidated by 1H n.m.r. spectroscopy with reference to conformation theory and the Woodward–Hoffmann rules. Unexplained differences in the 1H n.m.r. spectra of secosteroidal epoxides and episulphides are described.

Abstract Seventy-two steroids have been assayed for progestational activity in rabbits. Some of the steroids were also assayed for their antiestrogenic activity in rats and mice. Progesterone, administered subcutaneously, was used as the reference steroid in all tests. Three chemical manipulations consistently increased activity:- a) removal of the 10-methyl group, 1. b) introduction of an 11β-chloro group in 19-nor steroids, 2. c) introduction of a 16-methylene group.

AbstractUmsetzung des Androsten‐3,17‐dions (I) mit dem Diäthylaminderivat (II) ergibt unter Konfigurationswechsel das 11β‐Fluorid (III)(45% Ausbeute), Umsetzung von (I) mit (II) bei 0°C in Gegenwart eines Lithiumchlorid‐Überschusses mit Tetrahydrofuran ergibt das 11β‐Chlorid (IV) (85%), mit Lithiumbromid in Methylenchlorid das 11β‐Bromid (V) (57%).

11α-Hydroxy-19-nor-steroids react with N-(2-chloro-1,1,2-trifluoroethyl)diethylamine to give the 11β-fluoro-derivatives or, in presence of lithium chloride or lithium bromide, the 11β-chloro- and 11β-bromo-derivatives, respectively.