Gold(I)-Catalyzed Synthesis of 2,2'-Biindoles via One-Pot Double Cycloisomerization Strategy.

The first systematic, concise and target-directed gold(I)-catalyzed synthesis of a family of 2,2'-biindoles containing different substitution patterns is described. The developed protocol involves the synthesis of 1,3-diyne-anilines followed by a one-pot gold(I)-catalyzed double cycloisomerization, giving rise to an efficient, broad and general protocol to get different 2,2'-biindoles under mild reaction conditions. Due to the methodological restriction of present methods for accessing this class of compounds, herein we present our synthetic proposal which allowed the preparation of several examples of 2,2'-biindoles.

Divergent role of PIDA and PIFA in the AlX (X = Cl, Br) halogenation of 2-naphthol: a mechanistic study.

The reaction mechanism for the chlorination and bromination of 2-naphthol with PIDA or PIFA and AlX (X = Cl, Br), previously reported by our group, was elucidated via quantum chemical calculations using density functional theory. The chlorination mechanism using PIFA and AlCl demonstrated a better experimental and theoretical yield compared to using PIDA. Additionally, the lowest-energy chlorinating species was characterized by an equilibrium of Cl-I(Ph)-OTFA-AlCl and [Cl-I(Ph)][OTFA-AlCl], rather than PhICl being the active species.

A Metastable Semiquinone Molecular Switch Modulated by Ascorbate/O: A Study from a System Far-From-Equilibrium to Biological Assays in Mitochondria.

A molecular switch based on the metastable radical anion derived from a substituted heteroaryl quinone is described. Pyrrolyl quinone thiocyanate (PQ 9) showed an interaction with the fluoride anion that was visible to the naked eye and quantified by UV/vis and 1H and 13 C NMR. The metastable quinoid species formed by the interaction with F ("ON" state) showed a molecular switching effect autocontrolled by the presence of ascorbate ("OFF" state) and back to the "ON" state by an autooxidation process, measured by visible and UV/vis spectroscopy.

Differential Effect of 4-Benzo[] [1, 3]oxazines on the Proliferation of Breast Cancer Cell Lines.

Background: A family of 4-benzo[][1,3]oxazines were obtained from a group of -(2-alkynyl)aryl benzamides precursors via gold(I) catalysed chemoselective 6--dig C-O cyclization.

Method: The precursors and oxazines obtained were studied in breast cancer cell lines MCF-7, CAMA-1, HCC1954 and SKBR-3 with differential biological activity showing various degrees of inhibition with a notable effect for those that had an aryl substituted at C-2 of the molecules. 4-benzo[][1,3]oxazines showed an IC rating from 0.

Ningalins, Pyrrole-Bearing Metabolites Isolated from Didemnum spp. Synthesis and MDR-Reversion Activity in Cancer Therapy.

Multi-Drug Resistance (MDR) is one of the most frequent problems observed in the course of cancer chemotherapy. Cells under treatment, tend to develop survival mechanisms to drug-action thus generating drug-resistance. One of the most important mechanism to get it is the over expression of P-gp glycoprotein, which acts as an efflux-pump releasing the drug outside of the cancer cell.

Metformin, a biological and synthetic overview.

Metformin is the most widely known anti-hyperglycemic, officially acquired by the USA government in 1995 and in 2001 it became the most prescribed treatment for type II diabetes. But how did it become the must-use drug for this disease in such a short period of time? it all started with traditional medicine, by using a plant known as "goat's rue" for the reduction of blood glucose levels. Its use arose in 1918 and evolved to the metformin synthesis in laboratories a couple of years later, using very rudimentary methods which involved melting and strong heating.

Role of the nonribosomal peptide synthetase siderophore enzyme (Rfs) of in controlling the growth of fungal phytopathogens.

Dimorphic species of , which are cosmopolitan fungi belonging to subphylum Mucoromycotina, are metabolically versatile. Some species of are sources of biotechnological products, such as biodiesel from and expression of heterologous proteins from . Furthermore, has been described as a model for understanding mucormycosis infections.

Iodine(III) reagents for oxidative aromatic halogenation.

Iodine(III) reagents have attracted chemical relvance in organic synthesis by their use as safe, non-toxic, green and easy to handle reagents in different transformations. These characteristics make them important alternatives to procedures involving hazardous and harsh reaction conditions. Their versatility as oxidants has been exploited in the functionalization of different aromatic cores, which allow the introduction of several groups.

Gold(I)-Catalyzed Synthesis of 4-Benzo[][1,3]oxazines and Biological Evaluation of Activity in Breast Cancer Cells.

The first gold(I)-catalyzed cycloisomerization procedure applied to the synthesis of substituted 4-benzo[][1,3]oxazines has been developed starting from -(2-alkynyl)aryl benzamides. The chemoselective oxygen cyclization via the 6--dig pathway yielded the observed heterocycles in modest to good chemical yields under very mild reaction conditions. The obtained oxazines were assayed on the breast cancer (BC)-derived cell lines MCF-7 and HCC1954 with differential biological activity.

Novel 2-aryl-4-aryloxyquinoline-based fungistatics for Mucor circinelloides. Biological evaluation of activity, QSAR and docking study.

Zygomycetes are ubiquitous saprophytes in natural environments which transform organic matter. Some zygomycetes of gender Mucor have attracted interest in health sector. Due to its ability as opportunistic microorganisms infecting immuno-compromised people and to the few available pharmacological treatments, the mucormycosis is receiving worldwide attention.

Diaryliodonium(III) salts in one-pot double functionalization of C-I and C-H bonds.

Since the 1950s, diaryliodonium(III) salts have been demonstrated to participate in various arylation reactions, forming aryl-heteroatom and aryl-carbon bonds. Incorporating the arylation step into sequential transformations would provide access to complex molecules in short steps. This focus review summarizes the double functionalization of carbon-iodine(III) and carbon-hydrogen bonds using diaryliodonium(III) salts.

Myristic acid reduces skin inflammation and nociception.

This study evaluated the inhibitory effect of myristic acid (MA) on models of inflammation and nociception. The in vitro anti-inflammatory activities of MA were assessed on LPS-stimulated macrophages, membrane stabilization assay, and inhibition of protein denaturation, whereas the inhibitory activity of MA on in vivo inflammation was assessed on TPA-induced ear edema using acute and chronic assays in mice. The inhibitory effect of MA on nociception was assessed using three in vivo models.

A One-Pot Six-Component Reaction for the Synthesis of 1,5-Disubstituted Tetrazol-1,2,3-Triazole Hybrids and Their Cytotoxic Activity against the MCF-7 Cell Line.

A high-order multicomponent reaction involving a six-component reaction to obtain the novel linked 1,5-disubstituted tetrazole-1,2,3-triazole hybrids in low to moderate yield is described. This one-pot reaction is carried out under a cascade process consisting of three sequential reactions: Ugi-azide, bimolecular nucleophilic substitution (S2), and copper-catalyzed alkyne-azide reaction (CuAAC), with high atom and step-economy due the formation of six new bonds (one C-C, four C-N, and one N-N). Thus, the protocol developed offers operational simplicity, mild reaction conditions, and structural diversity.

Pharmacological activities of Asclepias curassavica L. (Apocynaceae) aerial parts.

Ethnopharmacological Relevance: Asclepias curassavica L. (Apocynaceae) is a perennial shrub used in the folk treatment of parasitism, pain, and inflammation.

Aim Of The Study: This work assessed the antiparasitic, anti-inflammatory, antinociceptive, and sedative effects of an ethanol extract from the aerial parts of Asclepias curassavica (ACE).

The Diaryliodonium(III) Salts Reaction With Free-Radicals Enables One-Pot Double Arylation of Naphthols.

The chemoselective reaction of the - followed by the centered naphthyl radicals with the more electron-deficient hypervalent bond of the diaryliodonium(III) salts is described. This discovered reactivity constitutes a new activation mode of the diaryliodonium(III) salts which enabled a one-pot doubly arylation of naphthols through the sequential - /O- bond formation. The naphthyl radicals were generated in the reaction by the tetramethylpiperidinyl radical (TMP·) which resulted from the homolytic fragmentation of the precursor TMPO.

Iodine(III)-Mediated, Controlled Di- or Monoiodination of Phenols.

An oxidative procedure for the electrophilic iodination of phenols was developed by using iodosylbenzene as a nontoxic iodine(III)-based oxidant and ammonium iodide as a cheap iodine atom source. A totally controlled monoiodination was achieved by buffering the reaction medium with KPO. This protocol proceeds with short reaction times, at mild temperatures, in an open flask, and generally with high yields.

Iodine(III)-Catalyzed Electrophilic Nitration of Phenols via Non-Brønsted Acidic NO Generation.

The first catalytic procedure for the electrophilic nitration of phenols was developed using iodosylbenzene as an organocatalyst based on iodine(III) and aluminum nitrate as a nitro group source. This atom-economic protocol occurs under mild, non-Brønsted acidic and open-flask reaction conditions with a broad functional-group tolerance including several heterocycles. Density functional theory (DFT) calculations at the (SMD:MeCN)Mo8-HX/(LANLo8+f,6-311+G*) level indicated that the reaction proceeds through a cationic pathway that efficiently generates the NO ion, which is the nitrating species under neutral conditions.

Self-treatment with herbal products for weight-loss among overweight and obese subjects from central Mexico.

Ethnopharmacological Relevance: Mexico ranks second in the world for obesity prevalence. In Mexico, obese and overweight subjects commonly seek alternative treatments for weight-loss, including the use of herbal products.

Aim Of The Study: The main objective of this study was to evaluate the prevalence of self-medication with herbal products for weight-loss among overweight and obese subjects residing in four states (Guanajuato, San Luis Potosi, State of Mexico, and Mexico City) from central Mexico.

Gold(i)-catalysed high-yielding synthesis of indenes by direct C-H bond activation.

A catalytic, practical and high-yielding procedure for the synthesis of indenes by direct Csp3-H activation under gold(i) catalysis was developed. The scope of the protocol was determined by synthesizing some electron-neutral, electron-poor as well as electron-rich derivatives including the dibenzofurane and carbazole heterocycles. The mechanism of this reaction was elucidated by theoretical calculations using a ONIOM(M08-HX/mixed-basis:PM6) hybrid scheme.

Total synthesis of kealiiquinone: the regio-controlled strategy for accessing its 1-methyl-4-arylbenzimidazolone core.

A practical, concise and straightforward total synthesis of kealiiquinone 1, a naphtho[2,3-]imidazole alkaloid obtained from the Micronesian marine sponge sp. was accomplished. The squaric acid chemistry to construct the 1,4-quinoid ring and the regioselective -methylation through a benzo[][1,2,5]selenadiazolium heterocycle are the key features in this report.

Protecting-Group-Free Total Synthesis and Biological Evaluation of 3-Methylkealiiquinone and Structural Analogues.

The modular protecting-group-free total synthesis of 3-methylkealiiquinone, an analogue of the marine alkaloid kealiiquinone, was accomplished in seven steps. A regioselectively constructed functionalized arylbenzimidazolone moiety and dimethyl squarate were used as the only two building blocks. A thermal ring expansion via 6π-conrotatory ring closure to build the quinone fragment gave rise to the desired linear analogue of the natural compound along with a nondescribed structurally attractive angular naphtho[1,2- d]imidazole regioisomer.

Practical, mild and efficient electrophilic bromination of phenols by a new I(iii)-based reagent: the PIDA-AlBr system.

A practical electrophilic bromination procedure for phenols and phenol-ethers was developed under efficient and very mild reaction conditions. A broad scope of arenes was investigated, including the benzimidazole and carbazole core as well as analgesics such as naproxen and paracetamol. The new I(iii)-based brominating reagent PhIOAcBr is operationally easy to prepare by mixing PIDA and AlBr.