bluuebunny/crossref_metadata_2025_split huggingface dataset:
Die Kinetik der thermischen Cyclisierung von 2,6‐Dimethyl‐1, cis‐3,5‐heptatrien in der Gasphase
Authors: Egger Kurt W. 
Published: December 2004

AbstractThe kinetics of the thermal cyclization of 2,6‐dimethyl‐1, cis‐3, 5‐heptatriene to 1, 5, 5‐trimethyl‐1, 3‐cyclohexadiene have been measured in the gas phase for temperatures ranging between 150.4 and 231.2°C. The observed reaction rates satisfy first order kinetics for pressures ranging between 2.5 and 25 torr. The reaction is homogeneous, as demonstrated by the insensitivity of the calculated rate constants towards a 13‐fold variation in the surface to volume ratio of the reaction vessels used. The least squares regression analysis of the observed rate constants yields (with standard errors) log kcycl. (s−1) = (10.50 ± 0.11) − (31.81 ± 0,24)/θ, where θ equals 4.58 × 10−3 T (°K).The trans isomer is stable under the reaction conditions used. The intramolecular reaction proceeds via a 6‐center cyclic transition state, involving a loss in entropy of ∼ 13.8 cal/°‐mole (based on the transition state formulation for unimolecular reactions, assuming a transmission coefficient of unity). When compared with estimated and with reported activation parameters for the cyclization of 1, cis‐3,5‐hexatriene, this amounts to an additional loss of ∼ 4.5 e.u., and an increase in Ea by ∼ 2 kcal/mole. This is attributed to the additional steric repulsions in the transition state, primarily owing to the methyl group in 6‐position.
Intramolekulare [2π + 2σ]‐Thermo‐cycloadditionen Synthese von Bis‐homo‐cyclopentadien‐Derivaten Vorläufige Mitteilung
Authors: Prinzbach H. , Martin H.‐D. 
Published: December 2004

AbstractIntramolecular thermal [2π + 2σ]‐cycloaddition reactions in the tricyclo[3.2.1.02,4]‐oct‐6‐ene system are described. Within a certain set of conditions no [2π + 2σ]‐additions within some tricyclo[5.1.0.03,5]octane derivatives could be achieved.
Die Strukturen der mittleren Ringverbindungen XV. 6‐Ketononanolid (Oxacyclodeca‐2,7‐dion)
Authors: Fedeli Walter , Dunitz J. D. 
Published: December 2004

AbstractCrystals of 6‐ketononanolide (oxacyclodeca‐2,6‐dione) are orthorhombic, a = 8.886, b = 16.407, c = 11.965 Å, space group Pbca, with 8 molecules in the unit cell. The structure has been solved with the help of direct methods and refined by full‐matrix least‐squares analysis of three‐dimensional intensity data. The conformation of the ring is similar to that previously observed in several cyclodecane derivatives, with the ring oxygen and carbonyl groups so situated as to minimize the number of transannular H … H contacts. Evidence for transannular O(ether) … C(carbonyl) donor‐acceptor attraction is discussed.
Synthèse des (±)‐loliolide, (±)‐actinidiolide, (±)‐dihydroactinidiolide et dérivés à partir d'acide homosafranique. Photooxygénation sensibilisée de I'homosafranate de méthyle
Authors: Demole Edouard , Enggist Paul 
Published: December 2004

AbstractWe have synthesized (±)‐loliolide (7 a), (±)‐actinidiolide (11 a), (±)‐dihydroactinidiolide (16), and (±)‐isodihydroactinidiolide (18) through various reaction paths starting from homosafranic acid (4 a). Thus, (±)‐actinidiolide has been synthesized for the first time, and this result allows to discard the alternative formula 11 b for that compound [2].By investigation of the sensitized photooxygenation of methyl homosafranate (4 b), this reaction is shown to lead to an interesting spiro‐peroxylactone 25, beside the expected endo‐peroxide 23. Specific oxygenation of the tetrasubstituted double bond of methyl homosafranate, and cyclisation of the hydroperoxide 24 thus produced, are believed to account for the formation of such a particular compound.The base‐catalysed rearrangement of the endo‐peroxide 23 gives rise to two compounds, one being the expected keto‐hydroxy‐ester 26. The other ‐ to which is assigned the glycidic ester structure 27 ‐ obviously results from an internal displacement reaction on oxygen in 23. It is note‐worthy that the sensitized photooxygenation of methyl homosafranate proceeds directly to the same glycidic ester when it is carried out in an alcaline solution.
Die Kristallstruktur eines 1:2‐Chrom(III)‐Komplexes vom Sandwichtypus
Authors: Joggi J. 
Published: December 2004

AbstractThe crystal structure of the triclinic modification of the 1:2 complex of chromium‐(III) with the azo dye from 3‐methyl‐anthranilic acid with 1‐(4‐bromophenyl)‐3‐methyl‐5‐pyrazolone has been determined. The space group is P1 with a = 13,46 Å, b = 14,79 Å, c = 12,56 Å, α = 62°30′, β = 106°51′ and γ = 98°25′. The structure was solved by the heavy atom technique and refined by blockdiagonal least squares method. The sandwich configuration postulated by SCHETTY [1] was confirmed.
Die Pyrrolizidin‐Alkaloide aus Senecio alpinus (L.) SCOP., S. subalpinus KOCH und S. incanus L. subsp. carniolicus, (WILLD.) BR.‐BL. Pyrrolizidin‐Alkaloide, 13. Mitteilung
Authors: Klásek A. , Reichstein T. , Šantavý F. 
Published: December 2004

AbstractSenecio alpinus (L.) SCOP. is very rich in alkaloids. The dried overground parts gave 0,45% crude alkaloid mixture. The main component is seneciphylline (1); small amounts of cristalline jacozine (4) could also be isolated. ‐ Senecio subalpinus KOCH gave 0,368% of crude alkaloid mixture. In contrast to former results only 0,1% of this was present in the form of N‐oxides. The bulk was a ca. 1 : 1 mixture of seneciphylline with senecionine (3). ‐ Senecio incanus L. subsp. carniolicus (WILLD) BRä.‐BL. gave 0,40% of crude alkaloid mixture; from this some pure seneciphylline could be isolated. ‐ In all three plants the presence of integerrimine (2) and other non‐identified alkaloids could be established by thin layer chromatography.
Modifikationen von Antibiotika. 2. Mitteilung [1]. Über die Darstellung von 7‐Amino‐cephalosporansäure
Authors: Fechtig B. , Peter H. , Bickel H. , Vischer E. 
Published: December 2004

Abstract7‐Aminocephalosporanic acid or esters thereof are prepared either by intramolecular aminolysis of esters of the antibiotic cephalosporin C or vïa imino‐ethers derived from the latter.A simple procedure for the preparation of 7‐aminocephalosporanic acid in high yield is described.
Reinigung und Kristallisation der Aldolase aus Drosophila melanogaster. 14. Mitteilung über Aldolasen [1]
Authors: Brenner‐Holzach O. , Leuthardt F. 
Published: December 2004

AbstractA method for the preparation of pure crystalline aldolase (type A) from pupae of Drosophila melanogaster is described.
Notiz zur Unterscheidung äquatorial‐äquatorial und äquatorial‐axial substituierter Cyclohexanderivate mit Hilfe der magneto‐optischen Rotationsdispersion (MORD.)
Authors: Wipf H.‐K. , Clerc J. T. , Simon W. 
Published: December 2004

AbstractMagneto‐optical rotatory dispersion (MORD.) measurements of disubstituted cyclohexane derivatives without heteroatoms show systematic differences between equatorial‐equatorial and equatorial‐axial substitution.
Optische Rotationsdispersion von Indolinalkaloiden mit Ketogruppen
Authors: Klyne W. , Swan R. J. , Gorman A. A. , Guggisberg A. , Schmid H. 
Published: December 2004

AbstractThe optical rotatory dispersion curves of a series of indolines, N(a)‐acetyl‐indolines and N(a)‐methoxycarbonyl‐indolines containing keto groups have been measured. It has been shown that the absolute stereochemistry of N(a)‐acetyl‐indolines containing keto groups can still be determined from the character of the Cotton Effect due to the aromatic chromophore, the ketone Cotton Effect however being more difficult to interpret. The use of N(a)‐methoxycarbonyl‐indoline and indoline chromophores is dangerous due to the complex nature of the Cotton Effect of the former and the overlapping of that of the latter with the ketone Cotton Effect.
Naturstoffe aus Mikroorganismen. 2. Mitteilung [1]. Isolierung von L‐Monapterin aus Pseudomonas roseus fluorescens J. C. MARCHAL 1937 und seine Konstitutionsaufklärung
Authors: Viscontini M. , Bühler‐Moor R. 
Published: December 2004

AbstractAus einer Kultur von Pseudomonas roseus fluorescens J. C. MARCHAL 1937 in eisenfreier, synthetischer Nährlösung wurde u.a. ein Pterin isoliert, das sich als (+)‐6‐(L‐threo‐1′,2′,3′‐Trihydroxypropyl)‐pterin erwiesen hat. ‐ Isolierung, Eigenschaften und Konstitutions‐aufklärung des Monapterins werden in dieser Arbeit beschrieben.
Naturstoffe aus Mikroorganismen. 3. Mitteilung [1]. Isolierung von 6‐Hydroxymethyl‐pterin aus Kulturen von Pseudomonas roseus fluorescens J. C. MARCHAL 1937
Authors: Viscontini M. , Frater‐Schroeder M. 
Published: December 2004

AbstractDie Isolierung des 6‐Hydroxymethyl‐pterins, neben anderen Pteridinen, aus Kulturen von Pseudomonas roseus fluorescens in synthetischer Nährlösung wird beschrieben. Die biologische Bedeutung dieses erstmals als reiner Stoff aus natürlicher Quelle isolierten Pterins wird geschildert.
Photoreaktionen von 5‐Phenyl‐pyrazolinen. Vorläufige Mitteilung
Authors: Rosenkranz H. J. , Schmid H. 
Published: December 2004

AbstractOn irradiation in benzene 1‐methyl‐5‐phenyl‐Δ2‐pyrazoline (1) is partly converted into trans‐ and cis‐1‐methylazo‐2‐phenyl‐cyclopropanes (2 and 3) in the ratio of 23:77. Both 2 and 3 on thermal treatment are reconverted to 1. A concurrent thermal equilibration of 2 and 3 is also observed. 1, 3‐Dimethyl‐5‐phenyl‐Δ2‐pyrazoline (5) on irradiation in benzene yields the corresponding trans‐ and cis‐1‐methylazo‐1‐methyl‐2‐phenyl‐cyclopropanes (6 and 7). In contrast similar treatment of 5‐phenyl‐Δ2‐pyrazoline gives benz‐ and cinnamaldazine (9 and 11) along with the corresponding mixed aldazine (10).
Über die sensibilisierte Photooxydation einiger cyclischer N‐Aryl‐enamine. 3. Mitteilung über Indole, Indolenine und Indoline
Authors: Pfoertner K. , Bernauer Karl 
Published: December 2004

AbstractEosine‐sensitized photooxidation of the cyclic N‐aryl‐enamines 1, 6 and 8 results in oxidative splitting of enamine double bonds. Thereby compounds 2, 7 and 9 respectively are formed. From a mixture of the tautomeric quinoline derivatives 12 and 13, on oxidation under similar conditions, the compounds 7, 14 and 16 were isolated.
Zur katalytischen Aktivität von Cu2+‐Komplexen mit vierzähnigen Liganden. Metall‐Ionen und h2o2, 18. Mitteilung
Authors: Erlenmeyer H. , Waldmeier P. , Sigel H. 
Published: December 2004

AbstractIn contrast to earlier reports [2] [8], the pure Cu2+ complex of phthalocyanine‐tetrasulfonic acid (I) is found to be inactive in the decomposition of H2O2. The Cu2+ complexes of 1, 4, 8, 11‐tetraazacyclotetradecan (II) and 2, 12‐dimethyl‐3,7,11,17‐tetraazabicyclo [11.3.1]‐heptadeca‐1(17), 2,11,13,15‐pentaen (III) are equally inactive. The results confirm that only Cu2+ complexes with a not «saturated» coordination sphere catalyse the decomposition of H2O2.
Herstellung und Eigenschaften von Oximen des 4‐Oxo‐4,5,6,7‐tetrahydroindols und ihre Umlagerung in Pyrrolo‐azepine 6. Mitteilung über synthetische Indol‐Verbindungen [1]
Authors: Stoll André P. , Troxler F. 
Published: December 2004

AbstractThe preparation and BECKMANN rearrangement of 4‐tosyloxyimino‐4,5,6,7‐tetrahydroindoles are described. The structures of the stereoisomeric parent oximes, their tosylates, and of the products of their BECKMANN rearrangement have been confirmed by NMR and IR spectroscopy.
Beiträge zur Chemie der Pyrrolo[3,2‐c]azepine und der Pyrrolo [3,2‐b]azepine
Authors: Troxler F. , Stoll André P. , Niklaus P. 
Published: December 2004

AbstractSome chemical transformations in the series of the pyrrolo [3,2‐b]azepines and the pyrrolo[3,2‐c]azepines are reported: alkylation at the pyrrolo nitrogen and/or the azepino nitrogen, reduction of the lactam group by means of LiAlH4, preparation of lactim ethers and amidines, substitution in position 2 by MANNICH reaction, bromination and condensation with oxalyl chloride or chloral hydrate, and the cyclocondensation with dimethylmalonyl chloride. The structures of the 2‐substitution products have been evaluated by NMR.‐spectroscopy.
Zur Biosynthese von Brefeldin A
Authors: Handschin U. , Sigg H. P. , Tamm Ch. 
Published: December 2004

AbstractBy feeding growing cultures of Penicillium brefeldianum Dodge with [‐14C]‐acetate radioactive brefeldin A (C16H24O4) was obtained. By extensive degradation of [14C]‐brefeldin A, the individual radioactivity of 12 of the 16 carbon atoms was determined quantitatively. The pattern of the distribution of the radioactivity shows that 8 acetate units have been incorporated into the metabolite in a regular manner. These findings suggest an octaketide as an intermediate. Possible mechanisms for the formation of the trans‐fused cyclopentane ring are discussed.
Steroide und Sexualhormone. 236. Mitteilung [1]. Die Synthese der 5α‐ und 5β‐17‐Oxo‐19‐hydroxy‐3‐aza‐3, 19‐cyclo‐A‐homo‐androstane
Authors: Binder R. , Wehrli H. 
Published: December 2004

AbstractThe synthesis of the novel title compounds (2 and 3) is described. These two isomers differ from structure 1, ascribed to the salamander alkaloid cycloneosamandione, with respect to ring A/B fusion and to the ketone position.
Fluorénacènes et fluorénaphènes Synthèses dans la série des indéno‐fluorènes XIII [1]. Dérivés phénylés du cis‐fluorénacène et du trans‐fluorénaphène
Authors: Chardonnens Louis , Chardonnens Henri 
Published: December 2004

AbstractA partir de la diéthylcétone et de l'α‐phénylchalcone on synthétise, en 6 étapes avec un rendement global de 24%, le phényl‐5‐dihydro‐10, 12‐indéno [2, 1‐b] fluorène, dérivé phénylé du cis‐fluorénacène. En partant de la diméthyl‐2, 6‐diphényl‐3, 5‐cyclohexène‐2‐one‐1, obtenue par condensation de la diéthylcétone sur la chalcone, on aboutit en 5 étapes simultanément au phényl‐11‐dihydro‐10, 12‐indéno [2, 1‐b]fluorène, autre dérivé du cis‐fluorénacène, et au phényl‐6‐dihydro‐7, 12‐indéno [1, 2‐a] fluorène, dérivé phénylé du trans‐fluorénaphène.
Menschliches Calcitonin. IV Die Synthese von Calcitonin M. Vorläufige Mitteilung
Authors: Sieber P. , Brugger M. , Kamber B. , Riniker B. , Rittel W. 
Published: December 2004

AbstractA preliminary account is giver of the synthesis of calcitonin M (I), isolated from human C‐cell tumour tissue [2] [3]. Identity of the synthetic and the natural hormone was established by thin‐layer chromatography, thin‐layer electrophoresis and conversion to oxidation products, as well as by reference to the pattern of tryptic degradation and by comparing the biological activity of the two hormones. The findings also afforded additional confirmation of the results of structural elucidation [1].In the synthesis of I, use was made of methods described previously [4] for the preparation of porcine α‐thyrocalcitonin, and also of a new method [5] which easily permits the formation of cyclic cystine peptides.
Zur Biosynthese des Dendrolasins, eines Inhaltsstoffes der Ameise Lasius fuliginosus LATR
Authors: Waldner E. E. , Schlatter C. H. , Schmid H. 
Published: December 2004

AbstractBy feeding the ant Lasius fuliginosus LATR. with [14C]‐1‐acetate, [14C]‐2‐acetate, [14C]‐2‐mevalonate, [14C]‐2‐mevalonate, [14C]‐1‐glucose and [14C]‐U‐glucose, incorporation ratios of 10−4 – 0,15% were obtained in the sesquiterpenoid dendrolasin. It was shown by analysis of the labelling pattern in dendrolasin that the insertions were spread over the whole molecule in exactly the manner that would be expected from terpene biosynthesis.
Umwandlung von Cardenoliden durch Mikroorganismen VI. 7β, 11α‐Dihydroxydigitoxigenin und Abbau von 7β‐Hydroxy‐digitoxigenin zum 3β, 7β‐Diacetoxy‐14‐hydroxy‐5β, 14β, 17αH‐ätiansäure‐methylester. Mitteilung über Reaktionen mit Mikroorganismen [1]
Authors: Scherrer‐Gervai M. , Gsell L. , Tamm Ch. 
Published: December 2004

AbstractDigitoxigenin (3) was transformed by a Fusarium spec. to 7β‐hydroxydigitoxigenin (1) 1β, 7β‐dihydroxydigitoxigenin (4) and to the hitherto unknown 7β, 11α‐dihydroxydigitoxigenin (9). 7β‐acetoxy‐digitoxigenin (2) was degraded to methyl 3β, 7β‐diacetoxy‐14‐hydroxy‐5β, 14β, 17αH‐etianate (11).
Photochemische Reaktionen 49. Mitteilung [1] Spezifisch π → π*‐induzierte Keton‐Photoreaktionen: Die Doppelbindungsverschiebung von O‐Acetyl‐10α‐testosteron Protonisierung der Doppelbindung seines δ5‐Isomeren
Authors: Kuwata S. , Schaffner K. 
Published: December 2004

AbstractThe α,β‐unsatured ketone 10α‐testosterone has been reported previously [6] to photoisomerize in t‐butanol solution to the β,γ‐unsaturated ketone. The irradiation had been carried out using a high‐pressure mercury lamp in a quartz vessel. For structural reasons this double bond shift cannot proceed through a photoenolization mechanism involving an intramolecular hydrogen transfer from the γ‐position to the enone oxygen as has been suggested to operate in several formally analogous cases of aliphatic enone isomerizations. In the present reinvestigation, O‐acetyl 10α‐testosterone (1) was used, employing selectively either excitation of its n → π* (with wavelengths > 300 nm) or its π → π* absorption band (with 253,7 nm).In t‐butanol solution the doublebond shift 1 → 2 could be effected with π→* excitation only. Experiments in deuterated solvent (t‐BuOD) resulted in deuterium in corporation in both the δ5‐ketone in the C(4)‐position, cf.(3) and in the conjugated ketone. These results indicate that the reactions is initiated either in the, Sπ,π* state or in a high vibrational mode of the S0 or tππ*state. n→ π* Excitation of 1 in t‐butanol gave essentially no over‐all chemical change, while in benzene solution it resulted again in a double bond isomerization (1 →2). In analogy to results with similar enones [28] under identical conditions the deconjugation in benzene may be the consequence of an intermolecular hydrogen abstraction of the Tn,π* excited state of the enone.Another specifically π →π* induced photoreaction was observed on irradiation of the β, γ‐unsaturated ketone 2 in t‐BuOD with 253,7 nm. The olefinic hydrogen at C‐6 of 2 was exchanged with deuterium and, to a small extent, isomerization to the conjugated ketone 1 with concomitant deuterium incorporation occurred. It is concluded that from the higher excited state of the β, γ‐unsaturated ketone, but not from its Sn,π* state, an activation mode of the double bond is accessible to effect D+ addition at C‐6 followed by deprotonation to 4 and to deuterated 1, respectively.
Recherches sur la formation et la transformation des esters LXXXI [1]. Sur la réaction d'isothiocyanates avec l'acide hydrazinoéthylphosphorique, et de l'isocyanate de phényle avec l'acide colaminephosphoreux
Authors: Rabinowitz Joseph , Chang Sherwood , Capurro Norine 
Published: December 2004

AbstractHydrazinoethyl phosphoric monoester has been prepared by reacting hydrazinoethanol with polyphosphoric acid, and isolated as di‐sodium salt.Sodium hydrazinoethyl phosphate reacts with phenylisothiocyanate (in H2O+ethanol) to yield mainly the derivative thiocarbamoylated at the substituted nitrogen atom. This derivative, heated for one night at 100° in 0.5 N HCl, is cyclized to 3‐amino‐2‐phenylimino‐thiazolidine in 62% yield. Sodium hydrazinoethyl phosphate reacts with o‐methoxycarbonylphenyl isothiocyanate (in H2O+dioxane) at the unsubstituted nitrogen atom to yield mainly the corresponding quinazoline derivative (IV, X = OPO3Na2). This derivative, heated for one night at 100° in 0.5 N HCl, is cyclized to 2‐o‐carboxyphenylamino‐dihydro‐δ2‐1, 3, 4‐thiadiazine (Va) in 55% yield (hydrolysis of the lactamic function as well).Aminoethyl phosphorous monoester (colaminephosphorous acid) reacted with phenylisocyanate (in H20+dioxane) in slightly alkaline medium (one equivalent of NaOH) yields sodium N‐phenylcarbamoylaminoethyl phosphite. Refluxed for 20 minutes in 1N NaOH, this carbamoyl derivative is not cyclized but only hydrolyzed to the open‐chained N‐phenyl‐N′‐hydroxyethylurea (VII).
Die Kristallstruktur eines polynuclearen Silber‐Platin‐Mercaptophosphin‐Komplexes
Authors: Strickler P. 
Published: December 2004

AbstractCrystals of Pt(S–CH2‐Ch2‐P(C2H5)2)2AgNO3 are orthorhombic, a = 14.814, b = 10.926, c = 12.298 Å, space group Pbon, Z = 4. The structure has been solved by FOURIER methods and refined by full‐matrix least‐squares analysis of three dimensional intensity data, measured on the HILGER & WATTS computer‐controlled 4‐circle diffractometer. The structure consists of infinite chains running along the c‐axis; each silver atom is coordinated almost linearly to two sulphur atoms belonging to the square‐planar coordination spheres of two different platinum atoms.
Notiz zur Veröffentlichung von M. VISCONTIN und R. PROVENZALE: «Herstellung von reinem (–)‐L‐Neopterin und (–)‐D‐Monapterin [1]»
Authors: Rembold H. 
Published: December 2004

AbstractEs wird auf vier massgebende, voneinander unabhängige Methoden zur Reinheitsprüfung von Polyhydroxyalkylpterinen hingewiesen. Die von REMBOLD et al. dargestellten Verbindungen genügen diesen Kriterien.
Synthese kernhydroxylierter Metaboliten des Dimetacrins
Authors: Molnar I. , Wagner‐Jauregg Th. 
Published: December 2004

AbstractTo prove the chemical structure of metabolites of the antidepressant drug (dimetacrin2) (Istonil®3), 2‐ and 3‐hydroxy‐9,9‐dimethyl‐10‐dimethylaminopropyl‐acridane and 2‐hydroxy‐monometacrin4 were synthesized using substituted alkoxy diphenylamines (V) as intermediates. The methoxy compounds on treatment with strong acids cyclized either to the corresponding acridanes or to their O‐demethylated derivatives, VI (X  OCH3 or OH), depending on concentration and temperature.
Untersuchungen über Steroide XLI. Umwandlungsprodukte des 17α‐Strophanthidins
Authors: Manzetti Aldo , Ehrenstein Maximilian 
Published: December 2004

AbstractPseudostrophanthidin (2) can be easily prepared by treating strophanthidin (1) with concentrated hydrochloric acid in the cold [1]. 2 has served as the initial product for the preparation of a number of analogues and homologues of steroid hormones [2] [3]. 17α‐Pseudostrophanthidin (4) is considered a suitable starting material for an extension of these investigations.It was logical to attempt the preparation of 4 from 17α‐strophanthidin (3) under conditions identical with those used in the conversion of 1 into 2. However, these experiments did not lead to 4 but, instead, by way of the unstable 14ξ‐chloro‐14‐deoxy‐17α‐strophanthidin (5) to 14‐anhydro‐17α‐strophanthidin (6). This result is essentially in agreement with findings reported in the literature [5]. To support the structure assigned to 6, this compound was also prepared by a different, unambiguous, route. Treatment of 3 with thionyl chloride in pyridine gave mainly 3β, 5β‐O, Osulfinyl‐14‐anhydro‐17α‐strophanthidin (8), which was converted into 6 by mild hydrolysis. In turn 6, as obtained via the unstable chloro compound 5, gave on treatment with thionyl chloride in pyridine a product identical with 8. – 6 was characterized as the 3‐acetate 7.As extension of these experiments, 17α‐strophanthidol (10) [6] was treated with concentrated hydrochloric acid in the cold under conditions similar to those used in the conversion of 3 into 6 by way of 5. This led to the isolation of 14‐anhydro‐17α‐strophanthidol (11), which could also be obtained by the reduction of 6 with aluminium amalgam.As is known [1] [8], strophanthidinic acid (13) can be converted into strophanthidinic acid 19,8‐lactone (14) by treatment with concentrated hydrochloric acid in the cold. In view of the negative results obtained in the attempt to transform 3 into 4 under these conditions, the question arose as to whether the conversion of 17α‐strophanthidinic acid (15) into 17α‐strophanthidinic acid 19,8‐lactone (16) by the same procedure is also impossible. 15 was prepared by treating 3 with hydrogen peroxide and was characterized as the methyl ester 17 and the methyl ester of the 3‐benzoate (18). 15 and 17 have been mentioned in the literature [5], but the physical constants reported differ from those obtained in this laboratory. It was demonstrated that after treating 15 with concentrated hydrochloric acid in the cold, no 16 could be isolated but, instead, an unstable chloro compound 19 which was converted into 14‐anhydro‐17α‐strophanthidinic acid (20). 20 was characterized as the methyl ester 21 and the 3‐acetate 22.