The synthesis of a new benzothiazine derivative, related to oxicams, synthesized from natural safrole

1 H-NMR Metabolomics Profiling and Volatile Content of 'Hoja Santa' (Piper auritum Kunth): A Millenary Edible Plant Consumed in Mexico

The leaves of Piper auritum Kunth ('Hoja Santa') have been consumed for centuries by native people of central and southern Mexico as a fresh vegetable or condiment. Herein we present the result of the ¹ H-NMR metabolomics profiling of three accessions of P. auritum harvested in three different provinces of Mexico (Puebla, Tlaxcala, and Oaxaca). The volatile content associated with the flavoring properties of the plant was also determined by GC/MS. The non-targeted metabolome of these samples revealed that P. auritum is a source of free essential amino acids such as isoleucine, leucine, threonine, valine, histidine, phenylalanine, and tryptophan as well as organic acids, free monosaccharides, and valuable nutraceuticals such as trigonelline, Myo-inositol, betaine, and choline. Principal component analysis and orthogonal partial least squares discriminated analysis of the metabolites found in P. auritum revealed trigonelline as the main differential compound found in the three studied accessions, suggesting this metabolite as a possible chemical marker. According to these statistical approaches, 60 % of the differential metabolites were provided by Oaxaca samples, suggesting that leaves harvested in this province have better (p<0.05) nutritional properties than the other samples analyzed. Nevertheless, the high abundance of the anti-nutrient safrole (90 %) in the volatile fraction, advises the potential toxicity of P. auritum consumed in Oaxaca. On the other hand, samples harvested in the northern highlands of Puebla, contained the lowest levels of safrole (30 %) and acceptable levels of nutrients and nutraceuticals including choline. From the three groups of studied plants, those harvested in the northern highlands from Puebla, could be considered safer for human consumption than the other analyzed accessions.

Design, Synthesis and Pharmacological Evaluation of Novel Conformationally Restricted N-arylpiperazine Derivatives Characterized as D2/D3 Receptor Ligands, Candidates for the Treatment of Neurodegenerative Diseases

Most neurodegenerative diseases are multifactorial, and the discovery of several molecular mechanisms related to their pathogenesis is constantly advancing. Dopamine and dopaminergic receptor subtypes are involved in the pathophysiology of several neurological disorders, such as schizophrenia, depression and drug addiction. For this reason, the dopaminergic system and dopamine receptor ligands play a key role in the treatment of such disorders. In this context, a novel series of conformationally restricted N-arylpiperazine derivatives (5a–f) with a good affinity for D₂/D₃ dopamine receptors is reported herein. Compounds were designed as interphenylene analogs of the drugs aripiprazole (2) and cariprazine (3), presenting a 1,3-benzodioxolyl subunit as a ligand of the secondary binding site of these receptors. The six new N-arylpiperazine compounds were synthesized in good yields by using classical methodologies, and binding and guanosine triphosphate (GTP)-shift studies were performed. Affinity values below 1 μM for both target receptors and distinct profiles of intrinsic efficacy were found. Docking studies revealed that Compounds 5a–f present a different binding mode with dopamine D₂ and D₃ receptors, mainly as a consequence of the conformational restriction imposed on the flexible spacer groups of 2 and 3.

Rhodium(iii)-catalyzed sulfonamide directed ortho C–H carbenoid functionalization via metal carbene migratory insertion

A rhodium(iii)-catalyzed sulfonamide directed ortho C–H carbenoid functionalization has been developed with good yields.

Use of receptor chimeras to identify small molecules with high affinity for the dynorphin A binding domain of the kappa opioid receptor

A series of 2-substituted sulfamoyl arylacetamides of general structure 2 were prepared as potent kappa opioid receptor agonists and the affinities of these compounds for opioid and chimeric receptors were compared with those of dynorphin A. Compounds 2e and 2i were identified as non-peptide small molecules that bound to chimeras 3 and 4 with high affinities similar to dynorphin A, resulting in K(i) values of 1.5 and 1.2 nM and 1.3 and 2.2 nM, respectively.

The Sulfonation of Safrole with Trimethylsilylchlorosulfonate as Sulfonating Agent

The sulfonation of naturally occurring safrole with trimethylsilylchlorosulfonate yielded three new sulfonated products, two sultones and a sulfonic acid the structures of which are discussed.

Synthesis and antiplatelet evaluation of novel aryl-sulfonamide derivatives, from natural safrole

In the scope of a research program aiming at the synthesis and pharmacological evaluation of novel possible antiplatelet prototype compounds, exploring bioisosterism principles for molecular design, we describe in this paper the synthesis of new aryl-sulfonamides derivatives, structurally similar to known thromboxane A2 receptor antagonists. The synthetic route used to access the new compounds described herein starts from safrole, an abundant Brazilian natural product, which occurs in Sassafras oil (Ocotea pretiosa). The results from preliminary evaluation of these novel aryl-sulfonamide compounds by the platelet aggregation inhibitory test, using rabbit PRP, induced by ADP, collagen, arachidonic acid, and U46619, identified the N-[2-(4-carboxymethoxyphenyl)ethyl]-6-methyl-3,4-methylenedioxyphe nyl- sulfonamido derivative as the most active among them, presenting in IC50 value for the U-46619-induced platelet aggregation in rabbit platelet-rich plasma: 329 microM.

Synthesis and pharmacological evaluation of new flosulide analogues, synthesized from natural safrole

Four new aryl-sulfonamide derivatives (3a, 4a, 5a-b), having methylenedioxy group attached to phenyl ring, were prepared from natural safrole and evaluated as anti-inflammatory agents. The N-methylsulfonamide 3a and corresponding retrosulfonamide derivative 5a were more active than standards indomethacin and nimesulide, at the same molar concentration, in carrageenan-induced pleurisy assay.

Synthesis and analgesic properties of 5-acyl-arylhydrazone 1-H pyrazolo [3,4-b] pyridine derivatives

A series of 5-acyl-arylhydrazone 1-H pyrazolo [3,4-b] pyridine derivatives (1), planned by applying classical ring isosterism, were synthesized in order to evaluate the structure-activity relationship (SAR), especially the participation of the structural acyl-arylhydrazone subunit in the analgesia. The synthetic route used produced the derivatives 1 in approximately 40% overall yield, using 9 as key intermediate. The results obtained from this study showed that in general the compounds of this series present a powerful analgesic activity in the test of abdominal contortions induced by acetic acid i.p. in albino mice, indicating the participation of the acyl-arylhydrazone moiety, as well the relevance of the substituent of the aryl ring, in the activity.