Abstract-The 13C NMR spectra of nearly 100 rnonoterpenes show thatthey ar every useful for the characterisation of these compounds. This method is especially valuable for the elucidation of stereochemical problems. With the exception of a few cases the observed chemical shifts follow the common rules. The problems with measurements using shift reagents are discussed.

Die Analyse der ' 3C-NMR-Spektren von 47 Chinohidinen und Piperidinen sowie einiger deuterierter Derivate gibt die Moglichkeit, die gefundenen Signale der Spektren mehrerer LupinenAlkaloide zuzuordnen. Die beobachteten chemischen Verschiebungen folgen im allgemeinen den iiblichen Regeln. Jedoch werden besondere Effekte beobachtet, die vor allem auf spezielle sterische Situationen zuriickzufuhren sind. Die Brauchbarkeit der '3C-NMR-Spektroskopie fur Lupinen-Alkaloide wird gezeigt. Lupin-Alkaloids, XLI') 13C-N.M.R. Spectra of Lupin-AlkaloidsThe analysis ofthe "C-n. m. r. spectra of47 quinolizidinesand piperidines as well as some deuterated derivatives give the possibility to coordinate the found signals of the spectra of several lupinalkaloids. The observed chemical shifts follow in general the common rules. However several particular effects can be recognized mainly due to special steric situations. The usefullness of 13C-n. m. r. spectroscopy for lupin-alkaloids has been shown.

Syntheses of Bile Pigments, XII. Synthesis of E,Z,Z‐Configurated Biliverdins from 5(1H)‐Pyrromethenones of the Same Configuration (Z,Z,Z)‐ and (E,Z,Z)‐mesobiliverdin IIIα dimethyl esters 4 are obtained by acid‐catalyzed condensation of methyl 5′‐(tert‐butoxycarbonyl)isoneoxanthobilirubinate with methyl (Z)‐ and (E)‐5′‐formylisoneoxanthobilirubinate, respectively.

Die I3C-NMR-Spektren mehrerer Polyine zeigen, daB die chernischen Verschiebungen aller Acetylen-W-Atome unterschiedlich sind, daher ist selbst beim Pentain 5 eine Zuordnung der Signale rnoglich. Die Verschiebungen unsymmetrisch substituierter Verbindungen stehen nur teilweise in ubereinstimrnung mit den zu erwartenden Elektronendichten. Bei Konjugation mit olefinischen C-Atomen beobachtet man eine Entschirmung des P-standigen Acetylen-C-Atoms. Die Beziehungen zwischen den Kopplungskonstanten und der Struktur werden diskutiert. Polyacetylenic Compounds, 2291) 13C N.M.R. Spectra of PolyynesThe I3C n.m.r. spectra of several polyynes show that the chemical shifts of all acetylenic "C-atoms differ from each other, so that even in the pentayne 5 a correlation of the signals is possible. The chemical shifts of unsymmetrically substituted compounds are only partly in agreement with the electron densities. In the case of conjugation with olefinic C-atoms a deshielding of the acetylenic C-atom in P-position is observed. The relationship between coupling constants and structure is discussed. ' ) J 3 -~c = 151.0, J4-H.C = 4.0. dl J&c = 133.0. J 4 -~c = 11.0, J3-H.C = 5.0, J~'-H,c 1.5. J4-H:c = 4.0, J4'-H,C = 3.0. 8 ) J 3 -~c = 150.0. h, J3-H.C = 9.0, Jy-H c = 1.5. kl J1-H.C = 133.0. m1 J]-H,c = 4.5, J]*-H.C 1.5. *) J3-H.C = 4.0, J3'-J3:C = 3.0. " JI-H:C = 11.5. n' J1-H.C = 3.0, J]*-H,

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