Experimental and theoretical study of electronic substituent effects in 4-aminoaryl (4-substituted aryl) sulphones

Abstract

Substituent effects o n the electronic structure of 23 biologically active 4-aminoaryl (4-substituted aryl) sulphones were investigated by means of 'H n.m.r., 13C n.m.r., and i.r. spectroscopy, as well as by semiempirical all-valence C N D 0 / 2 calculations, with and without sulphur d orbital participation. Good linear intercorrelations were found among the spectral data and between these and the computed electronic charges and the Hammett op values. On this basis the substituent effects are interpreted in terms of electronic charge perturbation, which is linearly transmitted from the substituent t o the whole molecule, bridging SO, group included. The agreement between experimental and theoretical data is good and the trends d o not depend on the inclusion or exclusion, in the calculations, of the sulphur d orbitals. Strong and linearly related o-n: electron interactions operate between C-1 and C-1' in the C( 1 )SO,C( 1 ') moiety; thus Koch and Moffitt's qualitative x-electron conjugation model for Case 2 type sulphones seems inadequate.

Designing dapsone polymer conjugates for controlled drug delivery

“…Although a modest yield is obtained, this simple and easy synthetic process of obtaining DapMa did not warrant further optimisation in order to increase the yield since sufficient amounts of the desired monomer could be easily obtained [17]. The 1 H and 13 C NMR peak assignment is presented in Section 3.1 and were further supported by the two-dimensional HMQC spectra ( Figure 4) and by previous works reporting NMR studies on (4-substituted aryl) sulfones which shown peak assignments in concordance with the reported here [19]. The amidation reaction was confirmed by the appearance of the bands corresponding to the methacrylic residue (5.8 and 5.5 ppm) and amide proton (10.1 ppm).…”

2-Azidomethyl-3-methyl-1-phenylsulfonyl-1H-indole

“…For the biological activity of compounds containing an indole ring system, sulfur and azides, see: Williams et al (1993); Amblard et al (2009); De-Benedetti et al (1985). For related structures, see: Fernandes et al (2005).…”

“…The Cu(I)-catalyzed 1,3-dipolar cycloaddition reaction between alkynes and azides has been suitable for the synthesis of a large number of modified nucleosides, nucleotides and oligonucleotides with a broad range of applications (Amblard et al, 2009). A lot of sulfur containing compounds, exhibit insecticidal, germicidal, antimicrobial and antibacterial activities (De-Benedetti et al, 1985).…”

2-[1-(Phenylsulfonyl)ethyl]benzoic acid and 2-[1-(phenylsulfonyl)propyl]benzoic acid

“…The title compounds, (I) and (II), are potential intermediates for the synthesis of 2-alkylbenzoic acid starting from o-toluic acid. Sulfates, sulfones, thiols, sulfonamides and sulfoxides are some of the compounds that belong to this class, and many of these exhibit insecticidal, germicidal or antimicrobial activities (Krishnaiah et al, 1995;De Benedetti et al, 1985;Dupont et al, 1978). Sulfur-containing compounds, for the most part, act as simple narcotics (Schultz et al, 2001).…”