75541-39-8Relevant academic research and scientific papers
Synthesis and microbiological evaluation of spiro piperidinyl heterocycles
Ramalingan,Balasubramanian,Kabilan,Vasudevan
, p. 41 - 55 (2007/10/03)
Some novel spiro piperidinyl heterocyclic compounds were synthesized and evaluated for their antibacterial activity against Staphylococcus aureus, Klepsiella pneumoniae, Bacillus subtilis, Escherichia coli and Pseudomonas aeruginosa and antifungal activit
Stereochemistry of Tetraaryl-3,7-diazabicyclononanes and Tetraaryl-1,3-diazaadamantanes
Quast, Helmut,Mueller, Bodo
, p. 2959 - 2975 (2007/10/02)
By means of paraformaldehyde, the 2,4,6,8-tetraaryl-3,7-diazabicyclononanones 7 = 19 of known constitution have been converted to the 1,3-diazaadamantanes 9 = 17 and 10 = 18, respectively, either directly or after previous Wolff-Kishner reduction.The IR and NMR spectra prove the rel-(2S, 4R, 6R, 8S)-configuration of the diazabicyclononanes 19 and 20 and the rel-(4R, 8S, 9R, 10S)-configuration of the corresponding 1,3-diazaadamantanes 17 and 18.These served as models in an 1H NMR spetroscopic investigation of the diazabicyclononanes 19 and 20, which exist in the chair-chair conformation, one chair having a pair of axial the other a pair of equatorial aryl groups.The reaction of the cis-2,6-diphenylpiperidone 6a with benzaldehyde or 4-methylbenzaldehyde and the reaction of 6b with benzaldehyde inevitably yielded mixtures of type 19, R4 = Ar14-nAr2n(n = 0-4), since in part the aldehydes are incorporated into the piperidones 6.The (equatorial) aryl groups of the piperidones 6 prefer the axial positions in the diazabicyclononanes 19.The diastereoselective formation of the diazabicyclononanes 21 and 22 is compared to that of 8-oxosparteine (27) and traced back to the greater stability of the all-trans-substituted piperidone intermediate trans-28.
