Mini-Reviews in Organic Chemistry - Volume 13, Issue 5, 2016

The severe side effects of currently available cancer therapies led focus on a natural product, Curcumin, which has been traditionally used in Indian medicine from centuries. Curcumin has potential to act against various diseases including cancer. This review describes, Curcumin as safe, multitargeted lead molecule in anticancer drug development, and current advances in chemical modification of the basic structure to overcome its limitations. Curcumin showed various biological activities including cancer chemoprevention and anticancer in vitro, in vivo and Phase I clinical trials. The improved solubility and potency of synthesized monocarbonyl analogues (MACs) and diarylidenylpiperidone (DAPs) analogs motivate the researchers to harness its safe, multitargeted and immune system modulator properties.

Cancer is becoming one of the leading causes of death in the world. In photodynamic therapy (PDT), highly reactive oxygen species (ROS) is usually produced to treat cancer by interaction of light with a PDT agent usually called photosensitizer (PS) and dissolved molecular oxygen. The therapeutic properties of light have been known for thousands of years in ancient time but the photodynamic therapy (PDT) was flourished only in the last century. It portrays the damage of living tissue by three essential components like photosensitizer, visible light and oxygen. The photosensitizer is a foreign molecule and a xenobiotic in nature usually administered into the bloodstream intravenously. In some cases, it is also applied to the body surface directly. Photosensitizers are generally classified as the first, second and third generations. In cancer treatment, targeting Subcellular organelles plays an important role as an excellent therapeutic strategy. Particularly the third generation PSs are the center of attraction for selectively targeting subcellular organelles in cancer therapy. Therefore, the subcellular organelles targeted by PS are studied to be a key parameter to make something clear the mechanism of PS-induced cytotoxity against cancer cell. A better understanding of the subcellular organelles and its environments may be the ultimate goal to prevent tumor growth and metastasis permanently through PDT. The main motivation for this review is to suggest alternatives for developing PS with better efficacy and greater targeting potential.

As a type of important monomers, α,ω-dienes can be (co)polymerized to afford the polymers with various microstructures. The cyclopolymerization of α,ω-dienes performs as an efficient method to obtain the cyclopolyolefins, which usually exhibit remarkable properties, such as high transparency, good mechanical properties, high glass transition temperature, etc.. Moreover, incomplete cyclopolymerization of α,ω-dienes affords the polymers bearing pendant vinyl groups, which can be modified by post-polymerization modification strategy to generate the functional polymers. Therefore, polymerization of α,ω-dienes has attracted extensive attention in both industrial and academic researches during recent decades. Through years of development, numerous single-site metal catalysts for coordination polymerization of α,ω-dienes have been reported, concerning group 3 metals, group 4 metals and some late transition metals. So, the aim of this review is to highlight these single-site metal catalysts which are used for coordination polymerization of α,ω-dienes.

Validation of new molecular entities and de novo drug discovery and development are traditional approaches of drug discovery which is costly and time consuming process. Thus, drug repositioning was an alternative approach to traditional drug discovery. Drug repositioning is also known as drug re-tasking, drug rescuing, therapeutic Switching, drug recycling, drug repurposing or drug reprofiling. It is a process or strategy of developing or discovering new therapeutic uses for failed or already marketed drug candidates/biologic/pro-drugs which maximize the therapeutic value of a drug and increase the success rates. With the increase in market competition, pharmaceutical companies are developing new drugs or new therapeutic uses, from existing/old/available drugs, by applying drug repositioning strategies, on target and off target concept, approaches and methods, which are less time consuming and less costly. However, drug repositioning faces multiple challenges which includes choosing the right therapeutic area for the test drugs of interest, issues related to clinical trials such as, need to run new trials from start if the data from the clinical or preclinical trials for the original drug or product are outdated or not satisfactory. Thus, with advancement in technology these challenges can be overcome and in future drug repositioning can provide a bright scope in providing new treatment options diseases.

4-Thiazolidinones are sulphur analogues of oxazolidines. They are heterocyclic ring systems which have been explored for their antimicrobial, anticancer, anti-HCV, antifungal, anticonvulsant, antituberculosis, and other activities. While some earlier reviews on the biological activities of this ring system have been reported, the present review describes more recent synthetic strategies and medicinal aspects of 4-thiazolidinones as anticancer agents reported during the past few years (2010-2016).

Members of the genus Rhodiola L. are perennial herbaceous plants indigenous to high altitudes in the Arctic, throughout the central Himalayan Mountain regions, Qinghai-Tibetan Plateau and to the European Alps. Nearly, 84 Rhodiola species (including subspecies and varieties) are recorded worldwide. For thousands of years, Rhodiola species has been in use as an important adaptogen, hemostatic, and tonic in traditional Tibetan medicines (TTM). The review describes the morphological characteristics of Rhodiola species, provides information about their distribution, summarizes the secondary metabolites of R. rosea that is the predominant species screened in efficacy studies, and compares the differences of secondary metabolites among other species such as R. crenulata, R. sachlinesis and R. sacra. Rhodiola L containing numerous active chemical compounds: phenyl propanoids, phenylethanol derivatives, flavanoids, terpenes, and phenolic acids. These compounds have important biological activities, such as adaptogenic/adaptogen, antioxidant, antifatigue, anticancer, postponing ageing, immunomodulatory, cardioprotective, metabolic effects, and antineuronal apoptosis effects.

In the past years, researchers successively isolated many chemically and biologically interesting secondary metabolites from marine Aspergillus. Marine Aspergillus is rich in novel nitrogenous compounds with strong bioactivities and has attracted attention in the fields of chemistry, pharmacology, physiology, medicine, etc. This report reviews 260 nitrogen-containing compounds from marine Aspergillus from 2010 to 2016. Natural products containing nitrogen from marine Aspergillus are of great significance for drug development, and may become an important source of medicinal natural products.

Protein tyrosine kinase (PTK) and tyrosine phosphatase (PTP) regulate various cellular processes. SHP-2, a ubiquitous non receptor type protein belongs to tyrosine phosphatase family. SHP-2 consists of two SH2 domain (N-SH2 and C-SH2), one C-terminal tail and a phosphatase domains. SHP2 is involved in regulating JAK-STAT and MAPK signaling pathways required for cell growth and differentiation. In the inactive form, SHP-2 is available in the closed conformation and gets activated after phosphorylation of tyrosine residues. SHP-2 protein is encoded with PTPN11 gene. Germline mutation in PTPN11 gene causes disruption in its closed conformation and causes over-expression of SHP-2 phosphatase activity. Deregulation of phosphatase activity leads to pathogenesis of cancer and diseases like Noonan and Leopard syndrome. Thus, SHP-2 inhibitors have been developed as a novel target for treating cancer and diseases caused due to abnormal cellular signaling. This review is a description of role of SHP-2 in cell physiology, diseases caused due to SHP-2 deregulation along with some SHP-2 inhibitors.