Dipolmomente und Konformation von 3- und 4-Brom- und Chlorheteracyclohexanen

Dipole Moments and Conformation of 3- and 4-Bromo and Chloro Heteracyclohexanes The dipole moments of some 3- and 4-bromo and chloro heteracyclohexanes are measured by the method of Debye and calculated both by the quantum-mechanical method CNDO/2 and vector addition method. The determination of conformational free energy is made on the basis of measured dipole moments μ of the conformation mixture and the calculated dipole moments μ_e and μ_a of the pure conformers. The results are discussed in relation to n.m.r.-results.     

ω-3- und ω-6-Fettsäuren – Biochemische Besonderheiten und biologische Wirkungen

ω-3- and ω-6-Fatty Acids – Biochemical Specialities and Biological Effects ω-6- and ω-3-fatty acids are essential for mammals and human beings. Deficiency symptoms of ω-6- and ω-3-fatty acids are known in infants and adults. In higher doses ω-6-and ω-3-fatty acids produce biological effects, which can have positive or negative consequences. Therefore a well balanced supply of these fatty acids must be considered. By a mixed diet according to the recommendations of the German Nutrition Society a sufficient supply with ω-6- and ω-3-fatty acids will be possible. In the present state of knowledge an uncontrolled medication of fish oil capsules cannot be recommended, but an increase of the present intake of salt water fish with a favourable type of fat and other useful nutrients like iodine, selenium et. is desirable.     

α- und γ-Tocopherol-Status und Fettsäurespektren in Seren von Vegetariern und Nichtvegetariern

α- and γ-Tocopherol Status and Fatty Acid Patterns in Serum Samples of Vegetarians and Non-Vegetarians A subsample (108 females, 70 males) of the Berlin vegetarian study was screened concerning the fatty acid patterns and the α- and γ-tocopherol levels of serum samples. Detailed diet-history (7-day-protocols) shows that vegetarians consume 35–40% more tocopherols than non-vegetarians. Concerning the fatty acids the uptake of polyunsaturated fatty acids (esp. linoleic acid) as well as the content of the serum is significantly higher in vegetarians than in age- and sex-matched controls. Despite the higher intake of tocopherols the serum levels of α-tocopherol show lower values for vegetarians (females: x = 11.01 mg/l, males: x = 8.91 mg/l) than for non-vegetarians (females: x? = 11.42 mg/l, males: x? = 10.55 mg/l). Possible causes for the differences observed could be the higher lipid status (total cholesterol, total glycerol) of non-vegetarians and/or the higher levels of linoleic acid in vegetarian sera.     

Synthese und Eigenschaften von 2-Methoxycarbonylmethylen- und 2- (Formyl-methoxycarbonylmethylen)-2H-Thiopyran-3-carbonsäureme-thylester

Synthesis and Properties of Methyl-2-methoxycarbonylmethylene- and -2-(formyl- methoxycarbonylmethylene)-2H-thiopyran-3-carboxylates Dimethyl-2-chloro-propene-l,3-dicarboxylate is a easily available reactive C₂-building block for the synthesis of 2H-thiopyran derivatives la — n in good yields via [C₃S + C₂]-cyclisation reactions using β-thioxoaldehydes and their derivatives as C₃S-synthons. The structure of the stable red products with Z-configuration (side chain in position 2 of the ring) is elucidated by means of several analytical and spectroscopic methods including X-ray analysis of compounds 1h and lk . Treating of 1 with Vilsmeier reagent yields title compounds 2 with a remarkable less reactive formyl group at the exo-methylene group. There is obviously a shielding effect of the carboxylate groups.     

Partialsynthesen von Cardenoliden und Cardenolid-Analogen. I. α,β- und β,γ-ungesättigte Lactonring-methylierte Cardenolide

Partial Syntheses of Cardenolides and Cardenolide Analogues. I. α,β- and β,γ-Unsaturated Lactone Ring-Methylated Cardenolides Base-catalyzed methylation of digitoxigenin 1a with methyl iodide and sodium hydride in DMF leads to the α,β-unsaturated cardenolides 2–5 and, after rearrangement of the CC-double bond, to the β,γ-unsaturated cardenolides 6 and 7 . Opening of the lactone ring results in the formation of 8 . Allylic oxidation of 4b affords the 14,21-epoxide 10 . Only the 22-methyl derivative 4a and its 3-O-tridigitoxoside 4d show strong biological effectivity, whereas methylation at 21R- or 21S-position results in considerable loss in activity.     

1H- und 13C-NMR-Spektren von N-Methyl-chinoliniumchalkonen: Bestimmung von σ-Konstanten für die 2-, 3- und 4-Position des N-Methyl-chinoliniumrings

¹H- and ¹³C-N.M.R. Spectra of N-Methyl-quinolinium Chalcones: Determination of σ-Constants for the 2-, 3- and 4-Position of the N-Methyl-quinolinium Ring For the N-methyl-quinolinium chalcones 1a – c the ¹H- and ¹³C-n.m.r. data are reported. The unambiguous assignment of signals is based upon the ¹H/¹H homoshift and the ¹³C/¹H heteroshift correlated 2D-n.m.r. spectra. Using a Hammett relationship we have determined σ-constants for the 2-, 3- and 4-position of the N-methyl-quinolinium ring from the ¹³C-α chemical shifts of 1a – c . Their comparison with the σ-values for the equivalent positions in the pyridine, N-methyl-pyridinium and quinoline ring indicates the additivity of anellation and quaternization effect.     

Gibberelline. XXXV. Synthese von neutralen und basischen Amiden der Gibberellin-A3- und -A1-Reihe

Gibberellins. XXXV. Synthesis of Neutral and Amino-substituted Amides of the Gibberellin A₃ and A₁ Series The synthesis of neutral and amino-substituted amides of the gibberellin A₃ and A₁ series via aminolysis of the corresponding gibberellin carboxylic acid anhydrides is described. The mass spectra and ¹H-NMR data of these compounds are discussed.     

Kristallinflüssige trans-4-(ω-Cyanalkyl)cyclohexylester und 4-(ω-Cyanalkyl)phenylester

Liquid Crystalline trans-4-(ω-Cyanalkyl)cyclohexylester and 4-(ω-Cyanalkyl)phenylesters The synthesis of the title esters 1 and 2a–e (n = 0 – 3) and their mesomorphic properties are described. When the alkyl-spacer n between the polar CN-group and the cyclohexane ring of cyanalkyl-cyclohexylesters 1 is increased the difference of the clearing points between the phenylesters 2 and the cyclohexylesters 1 decreases to nearly zero. The reason of higher clearing temperatures of 2 is a dynamic conformational effect of ring inversion of cyclohexane in the ester 1 with two polar substituents at the ring.     

Synthese und mesomorphe Eigenschaften von 4-[trans-4-n- Alkylcyclohexanoyloxy]-benzoesäurephenyl- und 4-Benzoyloxybenzoesäure-cyclohexylestern

Synthesis and Mesomorphic Properties of Phenyl 4-[trans-4-n-alkyl-cyclohexanoyloxy]-benzoates and Cyclohexyl-4-benzoyloxybenzoates Synthesis and liquid-crystalline properties of terminal and lateral substituted phenyl 4-[trans-4-n-alkylcyclohexanoyl-oxy]-benzoates 1–13 , cyclohexyl 4-benzoyloxybenzoates 14–17 and phenyl 4-benzoyloxybenzoates 18–23 are described. The effects of alicyclic part and of lateral substituents are discussed.     

Azole. 22.. 1H- und 13C-NMR Untersuchungen an isomeren 3- und 5-Amino-pyrazol-Derivaten

Azoles. 22. ¹H- and ¹³C-N.M.R. Investigation of Isomeric-3 and 5-Amino-Pyrazole Derivatives The ¹H- and ¹³C-n.m.r. spectra of nine pairs of isomeric 3- and 5-amino-pyrazole derivatives 1a — 1i and 2a — 2i and some of their acetylderivatives have been assigned and discussed. It has been found that ¹H- and ¹³C-n.m.r. spectroscopy is a useful tool for differentation of the above mentioned 3- and 5-amino-isomers.     

α-Substituierte Phosphonate. XXII. Synthese und NMR-Spektren offenkettiger und cyclischer Acetale von Formyl-phosphonsäureestern und Formyl-diphenylphosphinoxid

α-Substituted Phosphonates. XXII. Synthesis and N.M.R. Spectra of Open-chain and Cyclic Acetals of Formyl-phosphonic Acid Esters and Formyl-diphenylphosphinoxide The synthesis of characteristical examples of open-chain and cyclic alkyl-resp. arylacetals of formyl-phosphonic acid esters and of formyl-diphenylphosphinoxide by various methods is described. The ¹H-, ¹³C- and ³¹P-n.m.r.-spectra of this compounds and their dependence on the structure is discussed.