The authors describe a new technique for the subcutaneous heterotopic transplantation of the ovary before pelvic irradiation to treat Hodgkin's disease. Creation of a cavity to receive the transplant and the use of two surgical teams and the surgical microscope during the operation ensured its successful outcome. The transplanted ovary was followed up clinically and by ultrasound monitoring: ovarian cycles remained regular despite radiotherapy, and follicle growth occurred normally. In comparison to other types of oophoropexy described in the literature, the advantages of this technique included total protection of the ovary from irradiation, and conservation of ovarian function and fertility. One year after the procedure, puncture of the ovarian compartment produced a mature oocyte specimen.
13C-NMR. spectra of pterin, xanthopterin, isoxanthopterin, leucopterin, lumazinc and of the model compounds isocytosine and desamino-isocytosine have been measured as anions and cations in I M KaOD, CF&OOH, H,SO, and FSO,H solutions. The spectra were analysed by means of heteronuclear double resonance, with the aid of non-dccoupled spectra, and by spectral comparison. The results are interpreted in terms of the ionisation statc of the pteridines in the four solvents and are comparcd with those obtained from lK-NMR. spectroscopy.
1.Introductioin. -We have shown previously how IH-NMR. spectroscopy can be
The hydrolysis of 3,4-dimethylphospholium salts by thallium ethylate in alcohol yields exclusively the corresponding dienylphosphine oxides by ring opening in the general case. However when one of the phosphorus substituents is benzyl, the dienylphosphine oxide becomes the minor product of the hydrolysis, the major product being the 3-methyl-4-methylene-2-phospholene oxide which results from the cleavage of the P—CH2Ph bond with isomerization of one of the double bonds of the phosphole ring. Deuterolysis of benzylphospholium salts shows that the isomerization does not take place before the hydrolysis. Attempted reduction of the P=O bond of dienylphosphine oxides by phenylsilane yields hydrogenated products. On the contrary, the P=O → P=S conversion by P4S10 occurs without destruction of the dienic system. High yields of diene–Fe(CO)3 complexes are obtained by reaction with Fe3(CO)12. When the two phosphorus substituents are different, two diastereoisomeric complexes are obtained.
Colchicin und seine Abkommlinge konnen selektiv an C-I formyliert werden. Die neue Aldehydgruppe laBt sich schonend reduzieren und oxydieren. Das entsprechende Oxim fuhrt durch BECKMANNSChe Umlagerung zu 1 -Cyan-und 1 -Amino-Derivaten. Eine Serie von 33 neuen Abkommlingen des Colchicins ist so fur physiologische Versuche zuganglich geworden.In den zahlreichen Arbeiten uber Colchicin und seine Begleitsubstanzen findet man erstaunlich wenig Reaktionen, die den Ring A betreffen, obwohl ihn die drei Methoxygruppen fur elektrophile Angriffe besonders geeignet erscheinen lassen. Unseres Wissens sind bisher nur Nitrierungl) und Bromierungz) des Colchicins studiert worden, wobei die Lage der neuen Substituenten nicht mit Sicherheit bewiesen wurde. Grund dafur ist die g r o k Empfindlichkeit des Tropolonrhges, der diesen Reaktionen ebenfalls zuganglich ist.Beispiele dafur Iiefert das Tropolon selbst, das sich nitrosieren, halogenieren, mit Diazoniumsalzen kuppeln und, wie die Phenole, hydroxyrnethylieren IBBt3). Dagegen scheinen Alkylierung, Acylierung nach FRIEDEL-CRAFTS, FRlEssche Verschiebung und Formylierung nach GATTERMANN gescheitert zu sein3). Ebenso ungunstig verlaufen Reaktionen mit konzentrierten Sauren, z. B. Nitrierung und Sulfonierung. Diese Verminderung der Reaktionsfdhigkeit wurde auf die Bildung des Tropylium-Ions zuruckgefiihrt4)), das elektrophilen Reagenzien widersteht.Die Bildung der folgenden Resonanzstruktur ist auch fur Colchicin in Betracht zu ziehen und kann dessen Tropolonring C desaktivieren:. .~
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.