bluuebunny/crossref_metadata_2025_split huggingface dataset:
Zum Mechanismus der Photochemie von 2‐Alkylindazolen in wässerigen Lösungen
Authors: Heinzelmann Willy , Märky Michael , Gilgen Paul 
Published: December 2004

Mechanistic studies on the photochemistry of 2‐alkylindazoles in aqueous solutions.The photochemistry of 2‐alkylindazoles 1 in aqueous solutions is rather complex, the relative yields of different products being dependent on the pH‐value of the irradiated solution: In neutral or basic solutions (pH > 7) as well as in most of the organic solvents isomerization to 1‐alkyl‐benzimidazoles 2 takes place. In dilute sulfuric acid (pH 2–4) this reaction is suppressed and the dihydro‐azepinones 3 and 4 are formed. Irradiation in strongly acid solutions (pH < 1) yields the o‐amino‐acetophenones 5 (Scheme 1).The relative quantum yields of the photoproducts 2–5 have been measured as a function of the pH‐value of the irradiated solution (Fig. 1). A comparison of these yields with the protonation equilibrium of the indazole in its first excited singlet state (pK = 2.8) suggests that 2 and 3 are both photoproducts of the neutral indazole molecule, whereas 4 as well as 5 are formed from the protonated indazole.The rearrangement of the indazole 1 to the benzimidazole 2 proceeds via an intermediate 6, which can be produced in high concentrations by monochromatic irradiation of 1 at low temperatures. The thermal reactivity of this intermediate in dilute sulfuric acid could be investigated: At pH 8 the only product is the benzimidazole 2. With decreasing pH‐value increasing amounts of 3 are formed and at pH < 4 the formation of 2 is completely suppressed, the only product being the azepinone 3. Thus, 3 is a solvolysis product of the intermediate 6 (Scheme 2).The most probable primary product of singlet indazolium is the nitrenium ion 7. From this intermediate the formation of 5 can proceed in well‐known thermal reactions. The formation of 4 is possibly due to a further protonation equilibrium nitrenium‐nitrene. The nitrene 7 can be converted into the azepinone 4 via the azirine 8 (Scheme 3). The pK‐values of different indazoles and intermediates are listed in the Table.
Heterotricyclodecane XX (+)‐(1S, 3S, 6S, 8S)‐ und (−)‐(1R, 3R, 6R, 8R)‐2, 7‐Dioxa‐twista‐4,9‐dien
Authors: Ackermann Peter , Ganter Camille 
Published: December 2004

(+)‐(1S, 3S, 6S, 8S)‐ and (−)‐(1R, 3R, 6R, 8R)‐2,7‐dioxa‐twista‐4,9‐diene.A synthesis and the determination of the sense of chirality of (+)‐(1S, 3S, 6S, 8S)‐ and (−)‐(1R, 3R, 6R, 8R)‐2,7‐dioxa‐twista‐4,9‐diene ((+)‐5 and (−)‐5, respectively) is described.
Flash Pyrolysis of 4‐Arylmethylidene‐oxazolones and ‐isoxazolones. A Versatile Synthesis of Arylacetylenes. Preliminary communication
Authors: Wentrup Curt , Reichen Werner 
Published: December 2004

AbstractFlash pyrolysis of 4‐benzylidene‐2‐phenyl‐5(4H)‐oxazolone (1) yields carbonmonoxide, benzene, biphenyl, diphenylacetonitrile, and 2,3‐diphenylsuccinonitrile; N‐benzoylphenylketenimine is implicated as the primary intermediate. The flash pyrolysis of 4‐arylmethylidene‐3‐methyl‐5(4H)‐isoxazolones (3) yields carbon dioxide, acetonitrile, and phenylacetylenes substituted by alkoxy, chloro, dimethylamino, and hydroxy groups, in yields of 45–95%. Arylmethylidenecarbenes are implicated as intermediates.
Linear‐reactor‐infrared‐matrix and microwave spectroscopy of the cis‐2‐butene gas‐phase ozonolysis
Authors: Kühne Heinz , Forster Martin , Hulliger Jürg , Ruprecht Heidi , Bauder Alfred , Günthard Hans‐Heinrich 
Published: December 2004

AbstractInvestigation of the formation of complex products in the gas‐phase ozonolysis of cis,‐2‐butene by linear‐reactor‐infrared‐matrix and linear‐reactor‐microwave spectroscopy is reported. The following species have been unequivocally detected: secondary 2‐butene ozonide, acetic acid, peracetic acid, glycolaldehyde, dimethyl ketene, the simple and mixed anhydrides of formic and acetic acid, 2,3‐epoxybutane and 2‐butanone, besides polyatomic products already known. In contrast, the primary ozonide has been detectable neither by LR.‐MW. nor by LR.‐IR. Observation of both stereoisomeric epoxides and kinetic modelling are used to support the intermediate formation of the O'Neal‐Blumstein radical CH3CH(O2)CH(O)CH3 and the existence of a reaction channel in which the two carbon atoms of the C, C double bond of the olefin remain connected. As the dominant reaction path a mechanism with a Criegee type split into methyldioxirane (ethylidene peroxide) and acetaldehyde is considered and subsequently proposed to explain formation of many complex products by either unimolecular or bimolecular processes of the peroxide. For the reactions considered, thermochemical estimates of reaction enthalpies and activation data are included. Kinetic modelling for a partial reaction mechanism involving at least two different paths of decay of the O'Neal‐Blumstein biradical into Criegee‐type intermediates and the 2, 3‐epoxybutanes is discussed.
A Model for Nicotinamide‐Trytophane Charge‐Transfer Interactions: The complexation of nicotinamide‐ammonium salts by a macrocyclic receptor molecule bearing tryptophane side chains
Authors: Behr Jean‐Paul , Lehn Jean‐Marie 
Published: December 2004

AbstractThe complexation of primary ammonium salt substrates by macrocyclic polyether receptor molecules provides a general method for studying the nature and stereochemistry of intermolecular interactions. The substrates and receptors are fitted each with one of the interacting units and the resulting effects in the complex are analyzed. The method is used to study the biologically important indole‐pyridinium donor‐acceptor interaction. The complexes between macrocycles, bearing an indole group in side chains, and pyridinium‐ammonium salts display a characteristic charge‐transfer band. The absorption coefficients and stability constants have been determined. Competition experiments also provide a new method for measuring the stability constants of macrocycle‐ammonium complexes in organic solvents.
New Iridoid Glucosides and a Lignan Diglucoside from Globularia alypumL
Authors: Chaudhuri Ratan K. , Sticher Otto 
Published: December 2004

AbstractThe four new iridoid glucosides globularicisin (2), globularidin (5), globularimin (9), and globularinin (13), the lignan diglucoside liriodendrin (18), and syringin (20) have been isolated from Globularia alypum L. along with the previously reported glucosides globularin (1) and catalpol (4). Compound 2 is the first report of any cinnamoyl iridoid with a cis‐configuration at the acyl double bond. Compound 5 is another novel iridoid which lacks the characteristic C(3), C(4) double bond in the aglucone part. Compounds 9 and 13 are diastereomeric and contain highly oxygenated aglucone structures. The isolation of liriodendrin, from Globularia alypum is the first demonstration of the occurrence of a lignan in the family Globulariaceae.The structures have been elucidated by 1H‐ and 13C‐NMR. spectroscopy as well as by chemical transformations. Taxonomical significance of the cooccurrence of iridoid and lignan glycosides as well as the antileukemic potentiality of the latter are also appraised.
Ladroside (= 6′‐Caffeoyl‐mussaenoside), a New Iridoid Glucoside from Veronica officinalis L. (Scrophulariaceae) and the elucidation of the absolute configuration at C(8) of mussaenoside
Authors: Afifi‐Yazar Fatmaüu , Sticher Otto , Uesato Shinichi , Nagajima Kimiko , Inouye Hiroyuki 
Published: December 2004

AbstractA new iridoid glucoside, named ladroside, together with mussaenoside (1) [2], has been isolated from Veronica officinalis L. The structure of ladroside (4) and the identity of mussaenoside have been established by spectral analysis. Additionally, the absolute configuration at C(8) carrying the tertiary hydroxyl group has been established by chemical evidence.
Metallic Conductivity in Metal Tetraaza [14]Annulene Iodides: The Crystal Structures of Dihydrodibenzo‐[b, i]‐1, 4, 8, 11‐tetraazacyclotetradecinenickel and ‐palladium Iodides
Authors: Hunziker Max , Hilti Bruno , Rihs Grety 
Published: December 2004

AbstractSingle crystals of dihydrodibenzo[b, i]‐1, 4, 8, 11‐tetraazacyclotetradecinenickel iodide show metallic conductivity between room temperature and approx. 110 K. The crystals are orthorhombic, space group Ibam with four formula units per cell of the following dimensions: a = 20.245, b = 13.416, c = 6.418 Å. The analogous palladium complex is isomorphous, the cell constants being a = 20.452, b = 13.430 and c = 6.499 Å. A number of other partially oxidized metal tetraaza [14]annulenes also show electrical conductivity.
Reactions of Disulfides Derived from Penicillin Sulfoxides with Tertiary Phosphines in Presence of Carboxylic Acids
Authors: Prasad Kapa , Hamberger Helmut , Stüutz Peter , Schulz Gerhard 
Published: December 2004

AbstractA novel method for the preparation of thioesters starting from Iso‐Fujisawa disulfides is reported. The presence of an acylamino group cis to the disulfide function on the β‐lactam nucleus seems to be an essential requirement for this reaction. In the absence of such a cis‐acylamino group, desulfurization, is the preferred course.
Isolation and Structure of Pseurotin A, a Microbial Metabolite of Pseudeurotium ovalis STOLK with an Unusual Heterospirocyclic System
Authors: Bloch Peter , Tamm Christoph 
Published: December 2004

AbstractThe structure and absolute configuration of pseurotin A, a new metabolite, isolated from culture filtrates of Pseudeurotium ovalis STOLK (Ascomycetes) has been shown to be (1′S, 2′S, 5S, 8S, 9R, 3′Z)‐8‐benzoyl‐2 (1′,2‐dihydroxy‐3′‐hexenyl)‐9‐hydroxy‐8‐methoxy‐3‐methyl‐1‐oxa‐7‐azaspiro [4,4]non‐2‐ene‐4,6‐dione (1).
Visible Light Induced Water Cleavage in CdS Dispersions Loaded with Pt and RuO2, Hole Scavenging by RuO2
Authors: Kalyanasundaram Kuppuswamy , Borgarello Enrico , Gráutzel Michael 
Published: December 2004

AbstractIllumination of aqueous CdS dispersions loaded with Pt and RuO2 by visible light produces hydrogen and oxygen in stoichiometric proportion. No degradation of the photocatalyst is noted after 60 h of irradiation time. The RuO2 deposit on the particle surface greatly accelerates the transfer of holes from the semiconductor valence band to the aqueous solution thus inhibiting photocorrosion.
Über Pterinchemie. 77. Mitteilung)Das (6R,S)‐5‐Formyl‐6‐methyl‐5,6,7,8‐tetrahydropterin: Synthese, chemische und physikalisch‐chemische Eigenschaften
Authors: Ganguly Abhoy N. , Bieri Jost H. , Viscontini M. 
Published: December 2004

(6R,S)‐5‐Formyl‐6‐methyl‐5,6,7,8‐tetrahydropterine: Synthesis, Chemical and Physico‐chemical Properties(6R, S)‐5‐Formyl‐6‐methyl‐5,6,7,8‐tetrahydropterine (III), a model substance for the biologically important 6‐substituted 5‐formyl‐5,6,7,8‐tetrahydropterines, was obtained for the first time by formylation of the corresponding tetrahydropterine with formic acid. Compound III, analogously to the other known 5‐acyltetrahydropterines, exists in solution (except in DMSO) as a mixture of two rotamers IIIa and IIIb. The two H‐C(7) in III have the same chemical shift and the same coupling constant to H‐C(6), giving rise to a A,A',X,C‐system. Conformational analysis of III, based on its 1H‐NMR,‐spectrum, shows that the methyl group is pseudo‐axial and the formyl group pseudo‐equatorial. Moreover, the H(X)‐C(6) bond lies nearly in the plane bisecting the C(6)‐C(7)‐H(A), C(6)‐C(7)‐H(A') dihedral angle; the C(6) and C(7) lie outside the N(5)‐C(4a)‐C(8a) plane and the tetrahydropyrazine cycle must be extremely strained, according to Dreiding models.
Natural Occurrence of Enantiomeric and meso‐Astaxanthin. 5. Ex wild salmon (Salmo salar and Oncorhynchus)
Authors: Schiedt Katharina , Leuenberger Franz J. , Vecchi Max 
Published: December 2004

AbstractThe configurational isomers of astaxanthin (3,3′‐dihydroxy‐β,β‐carotene‐4,4′‐dione) from the flesh of salmon (Salmo salar and Oncorhynchus) caught at different places in Europe and Canada were isolated and analyzed as (−)‐camphanic acid diesters by means of HPLC. The biological variation in the composition of the configurational isomers in seven fish was surprisingly similar: 78 to 85% of (3S, 3′S)‐astaxanthin, 12 to 17% (3R, 3′R)‐astaxanthin and 2 to 6% meso‐astaxanthin.
Selektive Umfunktionalisierung der terminalen Amidgruppe offenkettiger Polyamide via 2‐Oxazolin‐5‐one als Zwischenstufen. Vorläufige Mitteilung
Authors: Obrecht Daniel , Heimgartner Heinz 
Published: December 2004

Selective Modification of the Terminal Amide Group of Linear Polyamides via 2‐Oxazolin‐5‐ones as IntermediatesTreatment of aqueous or alcoholic solutions of diamides of type 2 with HCl leads to the formation of amide‐acids and amide‐esters of type 3 (Scheme 1 and Table). It has been shown, that 2‐oxazolin‐5‐ones of type 4 are intermediates of this selective transformation of the disubstituted terminal amide group. The selectivity of the transformation is demonstrated by the reaction sequence shown in Scheme 3. No selectivity has been observed in the acid‐catalyzed hydrolysis of triamide 9 with a monosubstituted terminal amide group (Scheme 4). Hydrolysis of the optically active dipeptide derivatives (+)‐(L)‐13 and (+)‐(L)‐15 with HBr in nitromethane at 60–80° yields the pure enantiomer (+)‐(L)‐14 and (+)‐(L)‐16, respectively (Scheme 5), i.e., no racemization takes place under the reaction conditions.These results show the usefulness of the dimethylamide group as a protecting group for carboxylic acids for example in the peptide synthesis.
Complexes of Lanthanoid Nitrates with 15‐Crown‐5 and 18‐Crown‐6 Ethers
Authors: Bünzli Jean‐Claude G. , Wessner Denis 
Published: December 2004

Complexes between the heavier lanthanoid nitrates Ln(NO3)3 and 15‐crown‐5 (1) and 18‐crown‐6 (2) ethers were isolated and characterized. Both 1:1 and 4:3 complexes are formed with each Ln(III) ion, except in the case of Gd and 2. The thermal transformation of the 1:1 complexes into the corresponding 4:3 complexes was studied by thermogravimetry and by DSC, X‐ray and vibrational data provide information about the structure of these complexes. The interaction between Ln(III) ions and ligands 1 and 2 in non‐aqueous solutions is discussed on the basis of conductometric, fluorescence, UV./VIS. and 1H‐NMR. data. Only 1:1 complexes of 2 formed in solution and their formation constants range from logKf = 4.4 (Ln = La) to 2.4 (Ln = Yb); for Eu, Kf of the 15‐crown‐5 and 18‐crown‐6 ether complexes are of the same order of magnitude. For La, Pr, Nd, Eu, Yb, a variable temperature NMR. study gave some indications about the chemical exchanges in solution.The factors which determine the stoichiometry of the complexes are discussed.
Synthese und Charakterisierung der 8 isomeren, im Ring B mono‐ bzw. dihydroxylierten Royleanone
Authors: Meier Heidi , Rüedi Peter , Eugster Conrad Hans 
Published: December 2004

Synthesis and Characterization of the 8 Stereoisomeric Royleanones with One or Two Hydroxy Groups in Ring BThe partial syntheses of 6α, 7α‐dihydroxyroyleanone (6a), 6α, 7β‐dihydroxyroyleanone (7a) and 6β, 7β‐dihydroxyroyleanone (9a) are described. Thus, all in ring B mono‐ and dihydroxylated royleanones are now known (see [2–11]), being fully characterized by extensive spectroscopic, chiroptic and chromatographic (HPLC.) methods. An opening of the epoxyroyleanone 11a yields cis‐ and trans‐diols together with their corresponding mono‐ and di‐O‐acetyl derivatives. We postulate a reversible addition of the acetate ion at C(8) of the quinone system, followed by a neighbouring group participation of this O‐acetyl group.
Aromatization of 1‐Benzyltetrahydroisoquinolines: Racemization of (−)‐(S)‐(N‐nor)‐Reticuline
Authors: Buchs Peter , Brossi Arnold 
Published: December 2004

AbstractAromatization in the series of optically active 1‐benzyltetrahydroisoquinolines has been accomplished with (—)‐(S)−(N‐nor)‐reticuline (1b) and analogs. Direct catalytic or chemical reduction of the isoquinoline 4 obtained could not be achieved in a practical way but 4 was converted into 1 in three steps (4 → 8 → 9 → 1), in 55% overall yield. Partial O‐methylation of the isoquinoline 4 gave the isoquinoline alkaloid palaudine (5), before papaverine (6) was formed.
Stereoselektive Hydrid‐Reduktion von Tetronsäurederivaten. Synthese verzweigtkettiger Tetrofuranosen
Authors: Wyss Heinz , Vögeli Ulrich , Scheffold Rolf 
Published: December 2004

Stereoselective Hydride Reduction of Tetronic Acid Derivatives, Synthesis of Branched‐Chain TetrofuranosesThe 3‐methoxymethyl derivatives of 2‐methyl‐D, L‐threofuranose (10a) and 2‐deoxy‐2‐methyl‐D,L‐erythrofuranose (11a) are prepared starting from 2‐methyl‐tetronic acid (1). The key step is the stereoselective reduction of the 3‐oxo‐function of 2‐chloro‐2‐methyl‐3‐oxo‐γ‐butyrolacton (2) by sodiumborohydride, which proceeds predominantly anti with respect to the C,Cl‐bond. The configuration of the reduction products has been established by 1H‐ and 13C‐NMR.‐spectroscopy.
1‐Amino‐2‐phthalimido‐diazen‐1‐oxide: Bildung, Eigenschaften und Fragmentierungen in Imido‐ und Amino‐nitrene
Authors: Hoesch Lienhard 
Published: December 2004

1‐Amino‐2‐phthalimido‐diazene‐1‐oxides: Formation, Properties and Fragmentation Reactions into Imido‐ and Amino‐nitrenes1)Oxidatively generated phthalimido‐nitrene (1) reacts with the nitrosoamines 2a‐d (see Scheme 1) to give the corresponding (Z)‐1‐amino‐2‐phthalimido‐diazene‐1‐oxides 3a‐d in good yields. With the O‐nitroso compound 2e, no addition of the nitrene 1 took place.The constitution the adducts 3 (R = NR′2) is deduced from their spectroscopic properties (UV., IR., 1H‐NMR. and MS.) as compared to those of (Z)‐1‐aryl‐ and (Z)‐1‐alkyl‐2‐phthalimido‐diazene‐1‐oxides 3 (R = aryl and alkyl, resp.). The (Z)‐configuration of 3 (R = NR′2) follows from an X‐ray analysis which is reported separately.Compounds 3 (R = NR′2) are cleaved photolytically as well as by acid to the corresponding nitrosoamines 2 (R = NR′2) and the nitrene 1, which could be trapped by cyclohexene to give 40% of 7‐phthalimido‐7‐azabicyclo [4.1.0]heptane (8) and by dimethylsulfoxide to yield 96% of S, S‐dimethyl‐N‐phthalimido‐sulfoximide (13).Nucleophilic attack leads to fragmentation of 3 (R = NR′2) into derivatives of phthalic acid and degradation products of intermediate aminonitrenes 24 corresponding to the respective nitrosoamines 2 (R = NR′2) with loss of oxygen. A general rationalization for the formation of 24 includes as a key step of N‐ to C‐migration of the O‐atom (see Scheme 6). The final fate of 24 is depending on the type of the nucleophile used. Thus, hydrazinolysis of 3b and of 3c generates besides N, N′‐phthaloylhydrazine (15), morpholine (14) from 3b and 1, 3‐dihydroisoindole (16) together with 6′‐methylidene‐1, 2, 3, 4‐tetrahydronaphthalene‐2‐spiro‐1′‐cyclohexa‐2′, 4′‐diene (17) from 3c (see Scheme 5). Treatment of 3b and of 3c with sodium methylate leads in both reactions to monomethyl phthalate (33) and, with 3b, to 1, 2‐dimorpholinodiazene (31) and, with 3c, to 17 (see Scheme 7). Finally, the reaction of 3b with diethylamine generates N, N‐diethylphthalamic acid (36), morpholine (14), 1,1,4,4‐tetraethyl‐2‐tetrazene(34) and l,l‐diethyl‐4,4‐(3‐oxapentamethylene)‐2‐tetrazene (35) (see Scheme 8).
The Influence of Molecular Host Lattices on Electronic Properties of Orbitally (Near‐) Degenerate Transition Metal Complexes
Authors: Ammeter John H. , Zoller Linus , Bachmann Jürg , Baltzer Philippe , Gamp Eduard , Bucher René , Deiss Erich 
Published: December 2004

AbstractTransition metal complexes often have low‐lying excited electronic states and, as a consequence, tend to beelectronically labile, i.e., their electronic properties exhibit pronounced sensitivity to external perturbations. Often drastic changes in various spectroscopic properties indicating substantial electronic rearrangements can be induced be relatively weak intermolecular forces as provided by nonpolar solvents or solid molecular host lattices. This behaviour can be explained by crossing of potential surfaces in the vicinity of the absolute minimum. Many physical properties of a given orbitally (near‐) degenerate system depend strongly on the relative magnitude of some characteristic parameters determining the shape of the groundBorn‐Oppenheimerpotential surface(s),e.g.barrier heightversuszero‐point energy, distance between minimaversuszero‐point amplitude, energy difference between minima,etc.Typical examples are systems exhibitingJahn‐Telleractivity, spin‐crossover, mixed valence, exchange coupling and other types of electronic near‐degeneracies. In paramagnetic systems changes in the electronic wavefunction can be most conveniently detected and analyzed by using EPR. spectroscopy.In paramagnetic sandwich complexes we studied two types of orbital degeneracies:Jahn‐Tellerdegeneracies (d7‐systems such as Co (cp)2, Ni(cp)and Fe (cp) (bz), low‐spin d5‐systems such as Mn (cp)2) andlow‐spin/high‐spin equilibria(d5‐systems such as Mn (cp)2). By diluting these complexes and ring‐substituted derivatives in a large variety of diamagnetic host systems we have been able to control the6A/2E equilibrium of Mn (cp)2by influencing the metal‐to‐ring distance and by changing the degree of ring alkylation; similarly we have been able to vary the relative weights of the two electronic states contributing to the two‐fold degenerate electronic ground state of d5‐ and d7‐systems to a large degree by variation of the local asymmetric fields offered by the lattice sites of the host systems.For comparison the electronic ground state properties of octahedral Cu(II) complexes with CuN6CuO6chromophores, of V (CO)6and tetrahedral VCl4were also studied by EPR. between 4K and room temperature in several host systems. Characteristic differences in the details of the temperature and host dependence of the EPR. spectra in all these electronically labile systems can be explained in terms of differences in the vibronic coupling type (E⊗ evs.T ⊗ e, t), the strength of linear and/or quadraticJT‐coupling and the effects produced by spin‐orbit coupling.
Reaktionen von 2‐ und 3‐phenylsubstituierten Alkylakyliden‐iminium‐Ionen in der Gasphase. 5. Mitteilung über stossinduzierte Fragmentierungen von felddesorbierten Kationen
Authors: Fischer Matthias , Veith Hans Jürgen 
Published: December 2004

Reactions of 2‐ and 3‐Phenyl Substituted Alkylalkylidene Iminium Ions in the Gas PhaseThe collision‐induced fragmentations of 2‐ and 3‐phenyl substituted alkylalkylidene iminium ions are reported. Besides the homolytic cleavage of the azaallyl bond a nucleophilic attack of the unsubstituted phenyl group at the iminium function is observed in the gas phase, yielding carbonium ions such as cyclopropanspirobenzenium (3), indanylium (10) and indenylium ions (11).
A Stereocontrolled Access to (±)‐, (−)‐, and (+)‐Patchouli Alcohol
Authors: Näf Ferdinand , Decorzant René , Giersch Wolfgang , Ohloff Günther 
Published: December 2004

AbstractThe racemate and both enantiomers of patchouli alcohol have been synthesized by stereocontrolled routes. The olfactive properties of the patchouli alcohols prepared are reported.
Cyclizations of the C10 Fatty Acids from the Mandibulary Glands of the Honeybee Apis mellificaL.: Queen substance and royal jelly acid
Authors: Barbier Michel 
Published: December 2004

AbstractSeries of assays have been performed to cyclize the two main C10 aliphatic acids, (E)‐9‐oxo‐dec‐2‐enoic acid (3) (queen substance) and (E)‐10‐hydroxy‐dec‐2‐enoic acid (7) (royal jelly acid) produced by the mandibulary glands of the honeybee Apis mellifica L. Queen substance 3, resistant to thermocyclization, was cyclized by the action of polyphosphoric acid to the fulvene ketone 5. Triphenylphosphinediethyl azodicarboxylate treatment of royal jelly acid 7 mainly furnished the dilactide 6 together with a series of cyclic oligomers up to the pentamer. Attempts to favour the formation of the lactone 11 through other conditions failed, and thus the reaction does not seem suitable for the preparation of lactones using α, β‐unsaturated hydroxy acids.Substances 3,7,12,13,14,15, were submitted to in vitro antibacterial as well as growth inhibition tests but all results were negative at the concentrations reported.