166373-40-6Relevant academic research and scientific papers
Decomposition of N-hydroxylated compounds during atmospheric pressure chemical ionization
Eichenberger, Silvan,Meret, Michael,Bienz, Stefan,Bigler, Laurent
experimental part, p. 190 - 197 (2010/08/05)
N-Hydroxylated polyamine derivatives were found to decompose during the ionization process of liquid chromatography-atmospheric pressure chemical ionization-mass spectrometry (LC-APCI-MS) experiments. The phenomenon was studied with a model compound, a synthetic N-hydroxylated tetraamine derivative. It was found that reduction, oxidation and water elimination occurred during APCI to generate the corresponding amine, N-oxide, and imine. The investigation further revealed that decomposition of hydroxylamines during APCI depends upon the concentration of the analyte and on the acidity of the solution introduced into the ionization source. The pH-dependence of decomposition was utilized for the development of an MS method that allows for the unambiguous identification of N-OH functionalities. This method was applied for the study of natural products including polyamine toxins fromthevenomof thespider Agelenopsis aperta andmayfoline, a cyclic polyamine derivative of the shrub Maytenus buxifolia. Copyright
Conjugate addition of 6-membered hydrazine to chiral tert-butyl (E)-2-(p-tolylsulfinyl)cinnamates. Synthesis of (S)-celacinnine
Matsuyama,Itoh,Matsumoto,Ohira,Hara,Yoshida,Iyoda
, p. 2924 - 2930 (2007/10/03)
Two enantiomers of the bicyclic lactam, (S)- and (R)-9-phenyl-1,6-diazabicyclo[4.3.0]nonan-7-one (6), were synthesized stereoselectively with high optical purity (95% ee) by the asymmetric conjugate addition-cyclization of piperidazine to chiral vinyl sulfoxides, tert-butyl (E)-2-[(R)- and (S)-p-tolylsulfinyl]cinnamate (4), followed by removal of the p-tolylsulfinyl group with SmI2. The subsequent reductive cleavage of the N-N bond of the bicyclic lactam 6 with sodium in liquid ammonia produced the corresponding 9-membered azalactam, (S)- and (R)-4-phenyl-1,5-diazacyclononan-2-one (7) with 99% and 97% ee, respectively. X-ray crystallography showed that (S)-7 exists exclusively as a trans conformer in the crystal state. Starting from (S)-7, naturally occurring (S)-celacinnine 1 was synthesized with 99% ee employing the ring-expansion reaction via intramolecular transamidation.
Chiral vinyl sulfoxides as useful reagents for the synthesis of β-amino acid derivatives
Matsuyama, Haruo,Itoh, Nobuhiro,Yoshida, Masato,Iyoda, Masahiko
, p. 475 - 476 (2007/10/03)
(S)- and (R)-β-amino acid derivatives were synthesized by the asymmetric conjugate addition of ammonia and piperidazine to t-butyl (E)-2-[(R)-and (S)-p-tolylsulfinyl]cinnamates, respectively.
95. Asymmetric synthesis of the alkaloids mayfoline and N(1)-Acetyl-N(1)-deoxymayfoline
Kuehne, Paul,Linden, Anthony,Hesse, Manfred
, p. 1085 - 1094 (2007/10/03)
The total syntheses of the spermidine alkaloids (-)-mayfoline (11) and (+)-N(1)-acetyl-N(1)-deoxymayfoline (12) are described. These macrocyclic lactams belong to the most interesting conjugates of the polyamine derivatives very commonly found in nature. The enantioselective syntheses were achieved through resolution of the methyl 3-amino-3-phenylpropanoate (2) by recrystallization of its (+)-L-tartrate salt. Construction of the 13-membered ring ensued through condensation, reductive ring expansion (internal bond cleavage), and finally a transamidation reaction involving a second ring expansion.
ASYMMETRIC SYNTHESIS OF CELACINNINE UTILIZING OPTICALLY ACTIVE VINYL SULFOXIDES
Itoh, Nobuhiro,Matsuyama, Haruo,Yoshida, Masato,Kamigata, Nobumasa,Iyoda, Masahiko
, p. 415 - 418 (2007/10/02)
First asymmetric synthesis of celacinnine (10) was achieved from the nine-membered azalactam, 3-phenyl-4-azaoctanelactam (6), which was synthesized by the addition of piperidazine (4) to optically active vinyl sulfoxides (3).
