Structural, conformational and pharmacological study of some amides derived from 3-methyl-2,4-diphenyl-3-azabicyclo[3.3.1]nonan-9β-amine as potential analgesics

Synthesis, structural, conformational and pharmacological study of some amides derived from 3-methyl-2,4-diphenyl-3-azabicyclo[3.3.1]nonan-9α-amine

“…Furthermore, in the 13 C NMR spectra, the twin-chair conformation is confirmed by the C2(4) (73.86-73.89 ppm) and C6(8) (20.59-20.72 ppm) chemical shifts in agreement with previous work [4][5][6][7][8][9]. For a boat conformation, the carbon signals would be shifted to a higher field because of the steric compressing effect due to the eclipsing between H2(4) ax À H1(5) and H6(8) ax À H1(5) hydrogen atoms.…”

“…In the 1 H NMR spectra, the W 1/2 value (8-9 Hz) for the H1(5) signals is in agreement with previously reported values for a flattened chair-chair conformation in related bicyclic systems [4][5][6][7][8][9]. For a boat disposition of one of these rings, the signal corresponding to H1(5) would be an apparent doublet with a coupling constant about 18 Hz [10].…”

“…The N-CH 3 13 C chemical shifts of compounds 2-5 of about 44 ppm (Table 2) agree with the values found in equatorial N-CH 3 substituted piperidines [4][5][6][7][8][9]12]. Furthermore, in the 13 C NMR spectra, the twin-chair conformation is confirmed by the C2(4) (73.86-73.89 ppm) and C6(8) (20.59-20.72 ppm) chemical shifts in agreement with previous work [4][5][6][7][8][9].…”

“…Assignment of proton resonances for compounds 2-5 was made on the basis of our previous studies for related systems [4][5][6][7][8][9]. The 1 H NMR spectra of compounds 2-5 showed great similarity in relation to the bicyclic systems.…”

“…As continuation of our studies on the synthesis of heterocyclic compounds with potential therapeutic activity, we report in this paper the synthesis and the structural study of a series of amides (2)(3)(4)(5) derived from 3-methyl-2,4-diphenyl-3-azabicyclo[3.3.1]nonan-9a-amine (1) by IR and NMR spectroscopy. The unambiguous assignment of all proton and carbon resonances was achieved by double resonance experiments.…”