Synthesis and pharmacological evaluation of N-phenyl-acetamide sulfonamides designed as novel non-hepatotoxic analgesic candidates

Synthesis of typical sulfonamide antibiotics with [14C]- and [13C]-labeling on the phenyl ring for use in environmental studies

BACKGROUND

Due to their widespread use, sulfonamide antibiotics (SAs) have become ubiquitous environmental contaminants and thus a cause of public concern. However, a complete understanding of the behavior of these pollutants in complex environmental systems has been hampered by the unavailability and high cost of isotopically labeled SAs.

RESULTS

Using commercially available uniformly [¹⁴C]- and [¹³C]-labeled aniline as starting materials, we synthesized [phenyl-ring-¹⁴C]- and [phenyl-ring-¹³C]-labeled sulfamethoxazole (SMX), sulfamonomethoxine (SMM), and sulfadiazine (SDZ) in four-step (via the condensation of labeled N-acetylsulfanilyl chloride and aminoheterocycles) or five-step (via the condensation of labeled N-acetylsulfonamide and chloroheterocycles) reactions, with good yields (5.0-22.5% and 28.1-54.1% for [¹⁴C]- and [¹³C]-labeled SAs, respectively) and high purities (> 98.0%).

CONCLUSION

The synthesis of [¹⁴C]-labeled SAs in milligram amounts enables the preparation of labeled SAs with high specific radioactivity. The efficient and feasible methods described herein can be applied to the production of a variety of [¹⁴C]- or [¹³C]-labeled SAs for studies on their environmental behavior, including the fate, transformation, and bioaccumulation of these antibiotics in soils and aqueous systems.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1186/s12302-022-00598-z.

Recent investigations into synthesis and pharmacological activities of phenoxy acetamide and its derivatives (chalcone, indole and quinoline) as possible therapeutic candidates

Medicinal chemistry can rightfully be regarded as a cornerstone in the public health of our modern society that combines chemistry and pharmacology with the aim of designing and developing new pharmaceutical compounds. For this purpose, many chemical techniques as well as new computational chemistry applications are used to study the utilization of drugs and their biological effects. In the biological interface, medicinal chemistry constitutes a group of interdisciplinary sciences, as well as controlling its organic, physical and computational pillars. Therefore, medicinal chemists working to design an integrated and developing system that portends an era of novel and safe tailored drugs either by synthesizing new pharmaceuticals or to improving the processes by which existing pharmaceuticals are made. It includes researching the effects of synthetic, semi-synthetic and natural biologically active substances based on molecular interactions in terms of molecular structure with triggered functional groups or the specific physicochemical properties. The present work focuses on the literature survey of chemical diversity of phenoxy acetamide and its derivatives (Chalcone, Indole and Quinoline) in the molecular framework in order to get complete information regarding pharmacologically interesting compounds of widely different composition. From a biological and industrial point of view, this literature review may provide an opportunity for the chemists to design new derivatives of phenoxy acetamide and its derivatives that proved to be the successful agent in view of safety and efficacy to enhance life quality.

Intramolecular interactions, isomerization and vibrational frequencies of two paracetamol analogues: A spectroscopic and a computational approach

The aim of this investigation was to determine the molecular properties and provide an interpretation of the vibrational mode couplings of these two paracetamol analogues: 2-bromo-2-methyl-N-(4-nitrophenyl)-propanamide and 2-bromo-2-methyl-N-p-tolyl-propanamide. E/Z isomers, keto/enol unimolecular rearrangement and prediction of the transition state structures in each mechanism were also assessed using the Density Functional Theory (DFT). The DFT estimates a high energy gap between E and Z isomers (9-11 kcal·mol(-1)), with barrier heights ranging from 16 to 19 kcal·mol(-1). In contrast, the barrier energies on the keto/enol isomerization are almost 10 kcal·mol(-1) higher than those estimated for the E/Z rearrangement. The kinetic rate constant was also determined for each reaction mechanism. Natural bond orbital analysis and the quantum theory of atoms in molecules were used to interpret the intramolecular hydrogen bonds and to understand the most important interactions that govern the stabilization of each isomer. Furthermore, an analysis of the atomic charge distribution using different population methodologies was also performed.

Novel 2-chloro-4-anilino-quinazoline derivatives as EGFR and VEGFR-2 dual inhibitors

Novel 2-chloro-4-anilino-quinazolines designed as EGFR and VEGFR-2 dual inhibitors were synthesized and evaluated for inhibitory effects. EGFR and VEGFR-2 are validated targets in cancer therapy and combined inhibition might be synergistic for both antitumor activity and resistance prevention. The biological data obtained proved the potential of 2-chloro-4-anilino-quinazoline derivatives as EGFR and VEGFR-2 dual inhibitors, highlighting compound 8o, which was approximately 7-fold more potent on VEGFR-2 and approximately 11-fold more potent on EGFR compared to the prototype 7. SAR and docking studies allowed the identification of pharmacophoric groups for both kinases and demonstrated the importance of a hydrogen bond donor at the para position of the aniline moiety for interaction with conserved Glu and Asp amino acids in EGFR and VEGFR-2 binding sites.

THE SUBSTITUTION EFFECT ON THE AROMATICITY OF SOME N-PHENYLACETAMIDE DERIVATIVES: A DFT STUDY

The relative aromaticity of some N-phenylacetamide (NPA) derivatives were investigated in which the NPA was substituted by NO2, CN, CF3, Br, Cl, F, H, CH3 , and NH2 groups at two meta and para positions. For this purpose, density functional theory calculations were applied at the B3LYP/6-31+G(d,p) level to calculate the aromaticity indices including nucleus independent chemical shift (NICS), harmonic oscillator model of aromaticity (HOMA) and harmonic oscillator model of electron delocalization (HOMED). The obtained results indicated that the aromaticity of derivatives decreased in the order of NO 2 > CN > CF 3 > Br > Cl > F > H > CH 3 > NH 2 for both meta and para positions. Furthermore, the resulting order was directly related to the electron withdrawing and electron releasing strengths of the substituents. Finally, it was found that all the aromaticity indices of have a good correlation with the Hammett constant.

Synthesis and pharmacological evaluation of novel phenyl sulfonamide derivatives designed as modulators of pulmonary inflammatory response

In this paper we report the design, synthesis and pharmacological evaluation of a new series of phenyl sulfonamide derivatives 2a–h and 3–8 planned by structural modification on the anti-inflammatory prototype LASSBio-468 (1). Among the synthesized analogues, the tetrafluorophthalimide LASSBio-1439 (2e) stands out showing an in vitro anti-TNF-α effect similar to the standard thalidomide. The relevance of tetrafluorination of the phthalimide nucleus was also confirmed by the anti-inflammatory profile of 2e, through oral administration, in a murine model of pulmonary inflammation. The corresponding tetrafluorocarboxyamide metabolite LASSBio-1454 (15), generated from partial hydrolysis of the derivative 2e, presented a significant in vitro effect and a pronounced anti-inflammatory activity in vivo.

Structure-activity relationship studies of sulfonylpiperazine analogues as novel negative allosteric modulators of human neuronal nicotinic receptors

Neuronal nicotinic receptors have been implicated in several diseases and disorders such as autism, Alzheimer's disease, Parkinson's disease, epilepsy, and various forms of addiction. To understand the role of nicotinic receptors in these conditions, it would be beneficial to have selective molecules that target specific nicotinic receptors in vitro and in vivo. Our laboratory has previously identified novel negative allosteric modulators of human α4β2 (Hα4β2) and human α3β4 (Hα3β4) nicotinic receptors. The effects of novel sulfonylpiperazine analogues that act as negative allosteric modulators on both Hα4β2 nAChRs and Hα3β4 nAChRs were investigated. This work, through structure-activity relationship (SAR) studies, describes the chemical features of these molecules that are important for both potency and selectivity on Hα4β2 nAChRs.

Evaluation of the Bruker SMART X2S: crystallography for the nonspecialist?

An evaluation of the Bruker SMART X2S for the collection of crystallographic diffraction data, structure solution and refinement is carried out with a variety of materials with different electron densities, presenting some of the successes and challenges of automation in chemical crystallography.