bluuebunny/crossref_metadata_2025_split huggingface dataset:
Thermal and Photochemical Rearrangements of Divinylcyclopropanes to Cycloheptadienes. ‐ A model for the biosynthesis of the cycloheptadiene derivatives found in a seaweed (Dictyopteris). Preliminary communication
Authors: Pickenhagen Wilhelm , Näf Ferdinand , Ohloff Günther , Müller Paul , Perlberger Jean‐Claude 
Published: December 2004

AbstractThe activation parameters of the thermal rearrangements of the trans‐divinylcyclopropanes 1 and 2, and of cis‐divinylcyclopropane 3 to give cycloheptadiene 5 have been determined. In addition it has been shown that trans‐divinylcyclopropane‐cycloheptadiene rearrangements also occur under irradiation by a mercury lamp in benzene at 40°. These low‐temperature in vitro rearrangements suggest that the biosynthesis of the cycloheptadienes in Dictyopteris (dictyopterenes C′ and D′) may proceed by the same reaction(s).
Circulardichroismus. 62. Mitteilung. Chiroptische Eigenschaften einiger Trimethylcyclohexen‐Derivate: Die Jonone, Irone und Abszisinsäuren
Authors: Ohloff Günther , Otto Eberhard , Rautenstrauch Valentin , Snatzke Günther 
Published: December 2004

AbstractThe absolute configuration of (+)‐α‐ionone 3 (R), the absolute configurations at C(6) of (+)‐cis‐α‐irone 5 (6S) and (−)‐trans‐α‐irone 6 (6R), and the absolute configurations of (+)‐cis‐abscisic acid 10 (S) and (+)‐trans‐abscisic acid 11 (S) are deduced from the CD.‐spectra.
Steroide und Sexualhormone. 248. Mitteilung. Die Partialsynthese von 5α‐Dihydrohirundigenin und von 5α‐dihydroanhydrohirundigenin
Authors: Imhof René , Marti Franz , Schaffner Beat P. , Wehrli Hansuli 
Published: December 2004

AbstractA partial synthesis of dihydroanhydrohirundigenin (4), a hydrogenation product of naturally occurring anhydrohirundigenin (2) is described. Furthermore 4 is transformed into the formal dihydroderivative 14 of hirundigenin (1).
Die Photoelektronen‐Spektren des Tricyclo[4.2.1.02,5]nonadiens und seines 3,4‐Diaza‐Analogons. Ein Beitrag zur Kenntnis der Wechselwirkung zwischen den einsamen Elektronenpaaren der cis‐konfigurierten Azogruppe
Authors: Brogli Franz , Eberbach Wolfgang , Haselbach Edwin , Heilbronner Edgar , Hornung Volker , Lemal David M. 
Published: December 2004

AbstractA comparative photoelectron spectroscopical investigation of the title compound (11) and its 3,4‐ and 7,8‐dihydro derivatives (9 and 10) indicates that a considerable ‘through bond’ interaction exists between the π‐orbitals in 11. The PE. spectra of the 3,4‐diaza‐analogue of 10 and 11, which contain a cis azo group in a four‐membered ring, yield a splitting Δn (4‐memb. ring) = 1.55–1.60 eV between the nitrogen lone‐pair orbital energies. This value contrasts with those obtained for a three‐membered ring analogue (3,3‐dimethyldiazirine (5), Δn (3‐memb. ring) = 3.55 eV) and for a five‐membered ring analogue (2,3‐diazanorbornene (7) Δn(5‐memb. ring) = 3.10 eV). The sequence Δn (3‐memb. ring) > Δn (4‐memb. ring) Δn (5‐memb. ring) is satisfyingly reproduced by MINDO/2‐ and EHT‐calculations for the model systems with n = 3,4,5. A similar trend can be deduced from MINDO/2‐calculations for cis‐diimid where Δn becomes minimal for a NNH angle φ ≈ 100°, whereas Δn for the corresponding trans‐structure goes through a maximum in this region. The experimental finding as well as the calculated results confirm the predictions made by Gimarc [15] who attributes the behaviour of Δn for cis‐azo groups to a ‘through‐bond’ interaction of the n+‐orbital with a lowerlying NN σ‐orbital; this interaction becomes maximal for NNR angles of the size present in a fourmembered ring, e.g. in 12 or 13.
The Photolysis of Tricyclo[4.2.1.02,5]nonadiene: Support of a Doughert ‘type N’ mechanism from photoelectron spectroscopical studies
Authors: Haselbach Edwin , Eberbach Wolfgang 
Published: December 2004

AbstractIn earlier work on the photolysis of derivatives of tricyclo[4.2.1.02,5]nonadiene (I), the intermediacy of a biallyl‐like structure has been postulated which is formed by C1‐C2 bond cleavage of I in its first excited state. This mechanism is now supported by the results of photoelectron spectroscopical studies on I and its two dihydroderivatives. Further support is gained from the theoretically calculated Ehrenson C1‐C2‐bond indices for the ground and the first excited state of these molecules. While the results for I in principle can be rationalized on the (one‐electron) basis of ‘through bond’ interaction between the two π‐bonds, the absence of C1‐C2 photocleavage for a substituted tricyclo[4.2.2.02,5]decadiene also requires consideration of an (all‐electron) thermochemical driving force.
Heterotricyclodecane XVI. 2‐Oxa‐7‐aza‐isotwistane und 2‐Oxa‐7‐aza‐twistane
Authors: Portmann Robert Ernst , Ganter Camille 
Published: December 2004

AbstractThe synthesis of several derivatives of 2‐oxa‐7‐aza‐isotwistane (20–29 and 35) and 2‐oxa‐7‐twistane (30–34) is described starting from cis,cis‐cycloocta‐1, 5‐diene (1). The bicyclic acetoxy‐olefin 10 was used as a key intermediate.The 10N(7)‐isotwistane 22 was treated under reaction conditions suitable for molecular rearrangements involving an oxonium ion g, by neighbouring group participation, leading to 2‐oxa‐7‐aza‐twistanes.
Applications Synthétiques de la Cyclisation d′Alcools Tertiaires γ‐Éthyléniques en α‐Bromotétrahydrofurannes sous l'action du N‐Bromosuccinimide. III. Synthèse du Triméthyl‐2,6,10‐hydroxy‐10‐dodécatriène‐2,6,11‐al (trans/trans et trans/cis), Hydroxy‐Aldéhyde apparenté aux Sinensals
Authors: Demole Edouard , Enggist Paul 
Published: December 2004

AbstractThe reaction of 1‐formyl‐ethylidene‐triphenylphosphorane with trans‐ and cis‐4,8‐dimethyl‐8‐hydroxy‐deca‐4,9‐dienal (7) obtained from (±)‐nerolidol through a novel bromination/oxidation/debromination sequence, afforded 2,6,10‐trimethyl‐10‐hydroxy‐dodeca‐2,6‐11‐trienal 6 (trans‐2/trans‐6) and 10 (trans‐2/cis‐6), respectively. These hydroxyaldehydes closely related to the natural α‐ and β‐sinensals display a powerful, flower‐like odour.
Couplages J des groupes méthyle dans les phényltriméthylsilanes p‐substitués: Effets de solvants
Authors: Brouant P. , Limouzin Y. , Maire J. C. 
Published: December 2004

AbstractThe J coupling constants of a series of p‐substituted phenyltrimethylsilanes were measured in CH2Cl2 and CCl4 solutions. The solvent effect is discussed; it is too large to allow any straightward conclusion on ring‐substituent interaction.
Der A2+‐Mechanismus der säurekatalytischen Hydrolyse von Epoxiden und anderen cyklischen Oxa‐ Verbindungen
Authors: Willi Alfred V. 
Published: December 2004

AbstractIt is suggested that the acid catalyzed hydrolyses of isobutene oxide and propene oxide proceed via rate‐determining bimolecular reaction between a carbonium ion and solvent water (A2+ mechanism). The carbonium ion is formed by ring opening of the protonated epoxide, in a relatively fast preceding step. This mechanism is in agreement with all experimental facts known today. There is evidence for a similar mechanism in the acid catalyzed hydrolyses of cyclic acetals.
Bemerkung zur Gleichheit der Aufspaltungen ΔI (zwischen den ersten beiden π‐Ionisationspotentialen) und ΔE (zwischen den entsprechenden π* ← π Übergangsenergien) des Spiro[4,4]nonatetraens. Vorläufige Mitteilung
Authors: Batich Christopher , Heilbronner Edgar , Semmelhack Martin F. 
Published: December 2004

AbstractFor a given molecule M, the difference ΔI between the first two vertical ionization potentials Iv,2 and Iv,2 (from MOs ψ1 and ψ2) and ΔE between the corresponding singlet‐singlet excitation energies E1 and E2 (transitions ψ−1 ←1, ψ−1 ψ2) are related by ΔE = ΔI‐ (J2,−1−J1,−1) −2(K1,−1 − K2,−1), using Koopmans approximation. A simple MO model suggests that under certain conditions of symmetry and quasi‐alternancy (e. g. in spiro[4,4]nonatetraene 1) the bracketed differences between the Coulomb‐ and exchange‐integrals should vanish to first order, thus leading to the simple (almost) equality ΔE = ΔI. It is shown that the results from a photoelectron‐ and electron‐spectroscopic investigation of 1 support this conclusion i.e. ΔI = 1.23 eV, ΔE = 1.19 to 1.23 eV.
Photochemische Reaktionen. 75. Mitteilung. Die UV.‐Bestrahlung von 3β‐Acetoxy‐18‐dimethoxy‐20‐oxo‐Δ16‐5α‐pregnen
Authors: Marti Franz , Wehrli Hansuli , Jeger Oskar 
Published: December 2004

AbstractOn UV.‐irradiation in i‐octane the α,β‐unsaturated ketone 14 is transformed into a mixture of 15 and 16.
Chemistry of Succinylsuccinic Acid Derivatives. Part III. The Crystal and Molecular Structure of anti‐Tricyclo[4.4.01,6.07,12]‐1,4,7,10‐tetraethoxycarbonyl‐3,6,9,12‐tetrahydroxy‐dodeca‐3,9‐diene, C24H32O12, a Photodimer of Diethyl Succinylsuccinate
Authors: Mez Hans‐Christian , Rihs Greti 
Published: December 2004

AbstractX‐ray structure analysis of the title compound (II) is reported. Diffractometer data and the Faltmolekül method were used. Refinement converged at R 0.044. The molecule assumes the syn,syn‐conformation in the crystal.
The Stereoselectivity of Ketone Reduction with Sporotrichum Exile. Resolution of cis‐ and trans‐2‐benzoyloctahydro‐6(2H)‐isoquinolones
Authors: Uskoković M. R. , Pruess D. L. , Despreaux C. W. , Shiuey S. , Pizzolato G. , Gutzwiller J. 
Published: December 2004

AbstractDas 4a(S), 8a(R)‐Enantiomere des cis‐2‐Benzoyloctahydro‐6(2H)‐isochinolons wird durch Sporotrichum exile QM‐1250 unter anaerobischen Bedingungen achtmal schneller reduziert als das 4a(R), 8a(S)‐Enantiomere. Bei der entsprechenden trans‐Verbindung wurde diese Stereospezifität nicht beobachtet.
Acetolysis of 4‐endo‐diazoacetyl‐bicyclo[3.1.0]hexene: a new synthesis of semibullvalene. Preliminary communication
Authors: Malherbe Roger 
Published: December 2004

AbstractAcetolysis of diazoketone 1 gives in good yield 6‐acetoxy‐tricyclo[3.3.0.02,8]octan‐3‐one (2) which is converted into semibullvalene in a three‐step sequence. Compound 2 is potentially a good starting material for 3,6‐substituted semibullvalenes.
Absolute Konfiguration von β,ε‐Carotin‐2‐ol, β,β‐Carotin‐2‐ol und β,β‐Carotin‐2,2′‐diol
Authors: Buchecker Richard , Eugster Conrad Hans , Kjøsen Helge , Liaaen‐Jensen SynnøVe 
Published: December 2004

AbstractBy chemical degradation and application of the modified Horeau method the xanthophylls of Trentepohlia iolithus, namely 1a, 2a and 3a, have been shown to possess the (2 R, 6′ R)‐, (2R)‐, and (2R, 2′ R)‐configurations respectively.
Über Pterinchemie. 46., vorläufige Mitteilung. Identifizierung von substituierten Tetrahydropterinen durch Gas‐Chromatographie und Massenspektrometrie
Authors: Weber Rudolf , Frick Willi , Viscontini Max 
Published: December 2004

AbstractSilylierte, substituierte Tetrahydropterine lassen sich mit Hilfe der Glaskapillarchromatographie voneinander trennen. Die Kombination Glaskapillarchromatographie‐Massenspektrometrie erlaubt, die getrennten Tetrahydropterine zu identifizieren.
Sur les dérivés de la fluorénone VII. Bifluorényles et bifluorénonyles
Authors: Chardonnens Louis , De Blasi Vito , Rotzetter Armand 
Published: December 2004

AbstractStarting from 3‐bromo‐, 1‐iodo‐ and 4‐iodo‐9‐oxo‐fluorene three symmetrical bifluorenonyls and the corresponding hydrocarbons 3,3′‐, 1,1′‐ and 4,4′‐bifluorenyls are prepared. An attempt to obtain the non‐symmetrical 1,2′‐bifluorenyl is also described.
Kinetische Untersuchung der durch Imidazol katalysierten Acylübertragung von Thioestern auf Cyanessigester, einer Modellreaktion zur enzymatischen Knüpfung von C, C‐Bindungen
Authors: Wenck Helmut , Schallies Michael 
Published: December 2004

Abstract‐ Die durch Imidazol katalysierte Acylübertragung von Thioestern auf Cyanessigsäureäthylester in wässerigem Medium als Modellreaktion zur enzymatischen Knüpfung von C, C‐Bindungen besteht aus zwei Teilreaktionen: Bildung von N‐Acetylimidazol und Übertragung des Acylrestes auf den Acceptor. Letztere Teilreaktion ist spektroskopisch einheitlich. Mit dieser konkurriert die durch das entstehende RSH katalysierte Hydrolyse des N‐Acetylimidazols als Nebenreaktion. Hierdurch erklärt sich die gegenuber den beiden Teilschritten beträchtlich verminderte Geschwindigkeit der Gesamtreaktion.Bei konstantem pH nimmt. die Geschwindigkeitskonstante der Gesamtreaktion linear mit steigendem pKSHab.
Transition Metal Ions and Amides, VI. Complexation of the neutral and the anionic forms of 3, 7‐diazanonanedioic acid diamide and 3, 7‐diazanonanedioic acid diethylamide with Cu2+ and Ni2+
Authors: Kaden Thomas A. , Zuberbühler Andreas D. 
Published: December 2004

AbstractTwo tetradentate ligands, 3, 7‐diazanonanedioic acid diamide (DANA) and 3, 7‐diazanonanedioic acid diethylamide (DANEA) have been synthesized and their complexes with Cu2+ and Ni2+ studied potentiometrically and spectrophotometrically. Three monomeric species, ML, MH−1L, and MH−2L, are formed. In ML, the two carbonyl oxygens are bound to the metal ions. Whilst Cu2+ gives complexes CuH−1DANA+ and CuH−1DANEA+ with one deprotonated amide group, the corresponding Ni2+ chelates do not exist in detectable concentrations. CuH−2DANA and NiH−2DANA are formed below pH 9. In the case of the diethyl derivative DANEA, however, steric interaction strongly hinders coordination of two deprotonated amide groups.
Die Hysterese der Adsorptions‐ und Desorptionsisothermen an porösen Silicagelen und Aluminiumoxiden
Authors: Kohlschütter Hans Wolfgang , Lüscher Madeleine , Signer Rudolf 
Published: December 2004

AbstractIn selected groups of amorphous silica gels and finely crystalline aluminium oxides, hysteresis loops between the adsorption‐ and desorption isotherms of water were determined. The total volumes of the pore systems were analysed with the aid of the differential quotients of the hysteresis loops. In the group of silica gels relationships will be demonstrated between the precipitation of polysilicid acids and the distribution of the pore volume in the xerogels. In the group of aluminium oxides the influence of sintering at high temperatures on the distribution of the pore volume will be described.The hysteresis loops and especially the differential quotients distinctly differentiate specific properties of the used materials with their variables pore systems.An apparatus was used which recorded weights of water (= volumes and volume differences) with high sensitivity over the entire range p/po = 0 to 0,95. The appearance of hysteresis according to the fundamental theory was a sign that in this range adsorption and desorption of the liquid phase water took place in mesopores.
Reaktionskinetische Untersuchungen der Hydratisierung von Acetylen zu Acetaldehyd an Molekularsieben, die mit katalytisch wirksamen Metall‐Ionen beladen sind
Authors: Gut Günther , Aufdereggen Klaus 
Published: December 2004

AbstractThe kinetics of the catalytic hydration of acetylene to acetaldehyde in the gas‐phase by incorporation of catalytic metal ions on molecular sieves has been studied in a differential reactor. The main product was acetaldehyde besides of small amounts of crotonaldehyde and acetic acid. The catalysts [cadmium(II)‐, zinc(II)‐, copper(II)‐ and silver(I)‐13 X‐molecular sieves] were deactivated at a rate proportional to the square of the hydration rate. The initial hydration rate calculated on the basis of this relation was first order in the acetylene concentration. Starting rate of hydration and rate of deactivation increase with increasing concentration of metal ions on the sieve. The temperature dependence of the rate follows the law of Arrhenius The activation energies of hydration and deactivation, respectively, were calculated. Pore diffusion is a limiting factor. The poison is homogeneously deposited on the catalyst and weakly adsorbed, as it is shown by the criterion of Wheeler. The rate of deactivation decreases with increasing water/acetylene ratio. The deactivation rate which is due to deposition of polymerised acetylene and/or acetaldehyde, is slow with zinc and cadmium catalysts, and more rapid with copper and silver catalysts.
Quadricyclanes. Part II: Electronic structure and chemical reactivity
Authors: Haselbach Edwin , Martin Hans‐Dieter 
Published: December 2004

AbstractThe electronic structure of quadricyclane and 3‐methylidenequadricyclane obtained by photoelectron spectroscopy, is used as a basis for the discussion of cycloadditions to these systems. The electronic structure of 3‐heteroquadricyclanes, arrived at by theoretical calculations, agrees well with that expected from the above measured systems. A surprising outcome is that the orbital most responsible for the observed 2,4‐cycloadditions to these heterosystems in not the HOMO but the third highest orbital which lies well below the former. This strongly suggests that these 2,4‐cycloadditions proceed not in a concerted fashion but presumably involve as rate‐determining step the formation of a resonance‐stabilized zwitterionic intermediate. The nature of this intermeiate is discussed and the feasability of its formation investigated on the basis of thermochemical considerations.
The Crystal and Molecular Structure of 1‐Methyl‐1‐Thionia‐Cyclohexane Iodide
Authors: Gerdil Raymond 
Published: December 2004

AbstractCrystals of 1‐methyl‐1‐thionia‐cyclohexane iodide are orthorhombic with space group Pna21, a = 18.036, b = 6.611, c = 7.420 Å, Z = 4. The crystal structure was solved by the heavy‐atom method. Very strong parameter interactions prevented least‐squares refinement of atoms other than S and I. The molecule adopts the chair conformation with the methyl group in equatorial position.
Stereochemistry from X‐Ray Diffraction Studies of Three Palladium(II) Complexes with Terdentate Chelating Amines
Authors: Manohar Hattikudur , Schwarzenbach Dieter 
Published: December 2004

AbstractX‐ray crystal structure analysis of three Pd(II) complexes with cis‐3,5‐diaminopiperidine (DAPI) shows that the metal ion has a square planar coordination. The DAPI groups are trans in the protonated and mixed complexes. Most surprisingly, the unprotonated complex has a basket‐like structure with the DAPI groups cis.
Isolierung und Strukturaufklärung von Chlamydocin
Authors: Closse Annemarie , Huguenin René 
Published: December 2004

AbstractThe constitution of Chlamydocin – a metabolite of Diheterospora chlamydosporia with pronounced cytostatic activity – is proposed on the basis of chemical reactions and physical data. The synthesis of a derivative of a new amino acid is described. The biological activities of this compound and of derivatives of Chlamydocin are discussed.
Fluorénacènes et fluorénaphènes synthèses dans la série des indéno‐fluorènes, XVII. Dérivés méthylés du cis‐fluorénacène, du trans‐fluorénacène et du trans‐fluorénaphène
Authors: Chardonnens Louis , Laroche Bernard , Sieber Willy 
Published: December 2004

AbstractBy condensation of the chlorides of the three 9‐oxo‐fluorene‐2‐, ‐3‐, and ‐4‐carboxylic acids with 4‐bromo‐1,2‐xylene on one side, and of the chlorides of o‐bromobenzoic acid, 2‐bromo‐4‐methyl‐benzoic acid and 2‐bromo‐4,5‐dimethyl‐benzoic acid with fluorene, 2‐methylfluorene and 3‐methylfluorene on the other side, followed by direct or indirect cyclisation and by final reduction, several new methyl derivatives of the indenofluorenes I, II and IV are synthesized.
Absolute Konfiguration von Xanthophyll (Lutein)
Authors: Buchecker Richard , Hamm Peter , Eugster Conrad Hans 
Published: December 2004

AbstractAufgrund von Abbauresultaten an natürlichem (+)‐Xanthophyll (Lutein) und Xanthophylläthern und eingehender NMR.‐Analyse (insbesondere am Abbau‐Ionon V), Synthesen und chiroptischen Korrelationen wird bewiesen, dass (+)‐Xanthophyll (3R:3′R:6′R)‐Chiralität hat. Früher gemachte Vorschläge anderer Autoren sind zu korrigieren.Reduktion von Xanthophyll mit LiAlH4/AlCl3 gibt 3‐(R)‐Hydroxy‐3′,4′‐dehydro‐6(ξ)‐β,γ‐carotin. Mit 1‐Phenyl‐5‐chlortetrazol(Base) tritt Wasserabspaltung im β‐Ring zu 3,4‐Dehydro‐6′‐(R)‐3′‐(R)‐hydroxy‐β‐carotin ein.Die nun bekannte Chiralität von (+)‐Zeaxanthin ((3R:3′R)‐Dihydroxy‐β,β‐carotin) und von (+)‐Xanthophyll ((3R:3′R)‐Dihydroxy‐β,ϵ‐carotin) schliesst eine biologische Interconversion aus: sie würde meso‐Zeaxanthin ((3R:3′S)‐Dihydroxy‐β,β‐carotin) ergeben.Es wird eine Hypothese für die Hydroxylierung von ‐ bzw. α‐Carotin aufgestellt.
Eliminierungsreaktionen an Kationen in Gasphase II Essigsäureeliminierung aus Androstanylacetaten
Authors: Robbiani Richard , Seibl Josef 
Published: December 2004

AbstractElimination of acetic acid from the molecular ions of the epimeric androstanylacetates is investigated applying specific 2H‐labelling and analysis of metastable transitions. Only 17β‐androstanylacetate eliminates acetic acid in a 1,2‐fashion to an extent of 16%. This contribution is shown to be a specific cis‐elimination and after comparison with water‐elimination in the corresponding alcohol a McLafferty type mechanism is attributed, which then appears to require a planar transition state.
Studies of Organometallic Compounds XV. The Crystal Structure of Bis(tribenzyl‐titanium(IV))‐μ‐oxo
Authors: Stoeckli‐Evans Helen 
Published: December 2004

AbstractThe crystal and molecular structure of bis(tribenzyl‐titanium(IV))‐μ‐oxo, [(PhCH2)3‐Ti]2O, has been determined from analysis of X‐ray photographic data. The crystal system is rhombohedral, a = 9.58(2) Å, α = 83.6(2)°, space group R3, Z = 1.
The Mass Spectrometric Fragmentation of 1‐Alkyl Ions derived from Halides
Authors: Fiaux A. , Wirz B. , Gäumann T. 
Published: December 2004

AbstractThe mass‐spectrometric fragmentation of n‐pentyl, n‐hexyl, n‐octyl and n‐nonyl ions has been studied using 13C‐ and D‐labelling. The ions were produced from the corresponding halide ions. The loss of an olefin as a neutral fragment is the main reaction. The elimination of this fragment must be by a complex mechanism, since the terminal carbon atoms have the smallest probability of being lost with the neutral fragment. On chains with five to six carbon atoms, hydrogen scrambling seems to preceed the fragmentation; this is not true for hydrogen on terminal positions of longer chains. Ring formation prior to the fragmentation could explain some of the results; but no reasonable conclusion could be reached.
Welkstoffe und Antibiotika. 40. Mitteilung [1]. Synthesen von Dehydroorchinol‐methyläther und Dehydroorchinol
Authors: Müller Peter , Seres Josef , Steiner Kurt , Helali Salah E. , Hardegger Emil 
Published: December 2004

AbstractDie analytisch ermittelte Struktur des Orchinols als 2,4‐Dimethoxy‐7‐hydroxy‐9,10‐dihydrophenanthren wurde durch Synthese des Dehydroorchinol‐methyläthers (2,4,7‐Trimethoxyphenanthren) VIIIa und des Dehydroorchinols (2,4‐Dimethoxy‐7‐hydroxyphenanthren) VIIIc eindeutig bestätigt.