Immunomodulatory and anti-inflammatory and anticancer activities of porphyran, a sulfated galactan.

Seaweeds are high in bioactive chemicals frequently used to treat human illnesses. Porphyran is a polysaccharide found in the red seaweeds of the genus Porphyra. Porphyran has been discovered to have immunomodulatory, anti-inflammatory activity, and anti-cancer effects via boosting immunity and targeting important apoptotic molecules, making them potential chemotherapeutic or chemopreventive drugs. Polysaccharide-mediated dynamic control of apoptosis and autophagy in cancer has been a viable treatment with low cytotoxicity with high efficacy. Thus, comprehending the influence of porphyran on human health and their molecular mechanisms would open up a new paradigm in cancer therapies. Also, the importance of apoptotic/autophagy modulating porphyran in cancer therapy has been highlighted as the future direction of improved nano-formulation for improved clinical efficacy. This review focuses on the current research into porphyran's anti-cancer efficacy and putative mechanisms of action through apoptosis and autophagy in various cancers, as well as its potential chemotherapeutic treatment in near future.

MTP18 inhibition triggers mitochondrial hyperfusion to induce apoptosis through ROS-mediated lysosomal membrane permeabilization-dependent pathway in oral cancer.

Although stress-induced mitochondrial hyperfusion (SIMH) exerts a protective role in aiding cell survival, in the absence of mitochondrial fission, SIMH drives oxidative stress-related induction of apoptosis. In this study, our data showed that MTP18, a mitochondrial fission-promoting protein expression, was increased in oral cancer. We have screened and identified S28, a novel inhibitor of MTP18, which was found to induce SIMH and subsequently trigger apoptosis. Interestingly, it inhibited MTP18-mediated mitochondrial fission, as shown by a decrease in p-Drp1 along with increased Mfn1 expression in oral cancer cells. Moreover, S28 induced autophagy but not mitophagy due to the trouble in engulfment of hypoperfused mitochondria. Interestingly, S28-mediated SIMH resulted in the loss of mitochondrial membrane potential, leading to the consequent generation of mitochondrial superoxide to induce intrinsic apoptosis. Mechanistically, S28-induced mitochondrial superoxide caused lysosomal membrane permeabilization (LMP), resulting in decreased lysosomal pH, which impaired autophagosome-lysosome fusion. In this setting, it showed that overexpression of MTP18 resulted in mitochondrial fission leading to mitophagy and inhibition of superoxide-mediated LMP and apoptosis. Further, S28, in combination with FDA-approved anticancer drugs, exhibited higher apoptotic activity and decreased cell viability, suggesting the MTP18 inhibition combined with the anticancer drug could have greater efficacy against cancer.

Chemotherapeutic efficacy of curcumin and resveratrol against cancer: Chemoprevention, chemoprotection, drug synergism and clinical pharmacokinetics.

The frequent inefficiency of conventional cancer therapies due to drug resistance, non-targeted drug delivery, chemotherapy-associated toxic side effects turned the focus to bioactive phytochemicals. In this context, curcumin and resveratrol have emerged as potent chemopreventive and chemoprotective compounds modulating apoptotic and autophagic cell death pathways in cancer in vitro and in vivo. As synergistic agents in combination with clinically established anticancer drugs, the enhanced anticancer activity at reduced chemotherapy-associated toxicity towards normal organs can be explained by improved pharmacokinetics, pharmacodynamics, bioavailability and metabolism. With promising preclinical and clinical applications, the design of drug-loaded nanoparticles, nanocarriers, liposomes and micelles have gained much attention to improve target specificity and drug efficacy. The present review focuses on the molecular modes of chemoprevention, chemoprotection and drug synergism with special emphasis to preclinical and clinical applications, pharmacokinetics, pharmacodynamics and advanced drug delivery methods for the development of next-generation personalized cancer therapeutics.

CuMoO4 Bimetallic Nanoparticles, An Efficient Catalyst for Room Temperature C-S Cross-Coupling of Thiols and Haloarenes.

CuII catalyst is less efficient at room temperature for C-S cross-coupling. C-S cross-coupling by CuII catalyst at room temperature is not reported; however, doping of copper with molybdenum metal has been realized here to be more efficient for C-S cross-coupling in comparison to general CuII catalyst. The doped catalyst CuMoO4 nanoparticle is found to be more efficient than copper. The catalyst works under mild conditions without any ligand at room temperature and is recyclable and effective for a wide range of thiols and haloarenes (ArI, ArBr, ArF) from milligram to gram scale. The copper-based bimetallic catalyst is developed and recognized for C-S cross-coupling of haloarenes with alkyl and aryl thiols.

Metal-Free Activation of a C(sp)-H Bond of Aryl Acetylenes.

C(sp)-H Bond activation of acetylene molecule still remains a challenge for synthetic organic chemists. In practice, acetylenes are activated by strong bases and metals. The first example for activating acetylenic protons under base and metal-free conditions is reported here. It involves a general method for synthesizing propargylic derivatives of cotarnine. An array of tetrahydroisoquinolines alkaloids was synthesized by C(sp)-H bond activation of aromatic acetylenes with cotarnine at room temperature. A DFT-based mechanism is proposed for the reaction.

Activation of a carbonyl compound by halogen bonding.

Using a prototypical Diels-Alder reaction as benchmark, we show that dicationic halogen-bond donors are capable of activating a neutral organic substrate. By various comparison experiments, the action of traces of acid or of other structural features of the halogen-bond donor not related to halogen bonding are excluded with high certainty.

5-Iodo-1,2,3-triazolium-based multidentate halogen-bond donors as activating reagents.

Bi- and tridentate polycationic halogen bond donors based on 5-iodo-1,2,3-triazolium groups have been synthesized by 1,3-dipolar cycloaddition reactions. These halogen-based Lewis acids have been evaluated as activators in a halide-abstraction benchmark reaction.

Isothermal calorimetric titrations on charge-assisted halogen bonds: role of entropy, counterions, solvent, and temperature.

We have conducted isothermal calorimetric titrations to investigate the halogen-bond strength of cationic bidentate halogen-bond donors toward halides, using bis(iodoimidazolium) compounds as probes. These data are intended to aid the rational design of halogen-bond donors as well as the development of halogen-bond-based applications in solution. In all cases examined, the entropic contribution to the overall free energy of binding was found to be very important. The binding affinities showed little dependency on the weakly coordinating counteranions of the halogen-bond donors but became slightly stronger with higher temperatures. We also found a marked influence of different solvents on the interaction strength. The highest binding constant detected in this study was 3.3 × 10(6) M(-1).

Organocatalytic High Enantioselective Synthesis of ß-Formyl-α-hydroxyphosphonates.

The cross aldol reaction between enolizable aldehydes and α-ketophosphonates was achieved for the first time by using 9-amino-9-deoxy-epi-quinine as the catalyst. ß-Formyl-α-hydroxyphosphonates were obtained in high to excellent enantioselectivities. The reaction works especially well with acetaldehyde, which is a tough substrate for organocatalyzed cross aldol reactions. The products were demonstrated to have anticancer activities.

Synthesis of α-Arylphosphonates Using Copper-Catalyzed α-Arylation and Deacylative α-Arylation of ß-Ketophosphonates.

Efficient methods for the direct arylation and deacylative arylation of ß-ketophosphonates with iodoarenes in presence of a copper(I) or a copper(II) salt as the catalysts were developed. The corresponding α-arylphosphonates were obtained in high yields. A tentative mechanism for the deacylative arylation reaction was proposed on the basis of the experimental data.

CuO nanoparticles catalyzed C-N, C-O, and C-S cross-coupling reactions: scope and mechanism.

CuO nanoparticles have been studied for C-N, C-O, and C-S bond formations via cross-coupling reactions of nitrogen, oxygen, and sulfur nucleophiles with aryl halides. Amides, amines, imidazoles, phenols, alcohols and thiols undergo reactions with aryl iodides in the presence of a base such as KOH, Cs(2)CO(3), and K(2)CO(3) at moderate temperature. The procedure is simple, general, ligand-free, and efficient to afford the cross-coupled products in high yield.

Synthesis, structure, and application of self-assembled copper(II) aqua complex by H-bonding for acceleration of the nitroaldol reaction on water.

Simple addition: Copper(II) aqua complex 1 can be prepared in a one-pot synthesis and is self-assembled by H-bond interactions. Complex 1 is shown to accelerate the nitroaldol reaction on water, which is a heterogeneous process, requiring no additive or base, and 1 can be recycled without loss of activity. Copper(II) aqua complex 1 has been prepared in a one-pot synthesis. The single crystal X-ray analysis showed that the complex is self-assembled through aqua ligands by H-bond interactions and the copper(II) atoms are pentacoordinated with square pyramidal geometry. Complex 1 has been studied for the acceleration of the nitroalodol reaction on water. It is a clean technological process and the catalyst can be recycled without loss of activity.

Synthesis, structure and application of chiral copper(II) coordination polymers for asymmetric acylation.

Chiral copper(II) coordination polymers 1a-c have been prepared by one-pot synthesis in high yield. Their single-crystal X-ray analysis showed that repeating units are connected to each other by carboxylate linker and copper(II) atoms are pentacoordinated with distorted square-pyramidal geometry for 1a-b and square-planar geometry for 1c. These polymers have catalyzed the kinetic resolution of secondary alcohols by acylation with up to 90% ee ( s = 50).

Novel CuO nanoparticle catalyzed C-N cross coupling of amines with iodobenzene.

CuO nanoparticles catalyze the C-N cross coupling of amines with iodobenzene in excellent yields. The reaction is simple and efficient and operates under air with ligand free conditions. The catalyst is recyclable without loss of activity.