Mini Reviews in Medicinal Chemistry - Volume 15, Issue 9, 2015

This review covers the 2003-2012 literature data published for natural products originating from marine red algae. The focus is on new antitumour substances, together with details related to the organism sourced. It emphasises 14 promising compounds (isolated from 13 species) whose chemical structures are briefly discussed.

Histone Deacetylase (HDAC) is an established and validated target for the treatment of cancer. It has been attempted to present a comprehensive review on the inhibitors for Class-I Histone Deacetylase enzyme family, reported during the period from 2002 to 2012. This review has summarized the inhibitors, based on their specificity towards different isoforms within this class. Further various recent United State (US) patents and the HDAC inhibitors, used singly or in combination undergoing clinical trial as anticancer agents have been reviewed. Three such inhibitors SAHA, Romidepsin and Belinostat have already been approved by the US-FDA for the treatment of cancer.

Polymer drug conjugates play an important role in the delivery of drugs. In the polymeric drug conjugates, the bioactive agent is combined covalently with polymer to achieve the efficient delivery of bioactive agents in the required or specific period of time along with the enhancement of permeability and retention time. A large number of biodegradable polymers have been widely used in the area of biomedical science. Among them, polyphosphazene, is a biodegradable polymer having versatile nature because of its two chlorine atoms attached on both sides of phosphorus atom of its polymeric backbone, it can be easily replaced by nucleophilic substitution reaction. A plenty of work has been explored for its biomedical applications such as tissue engineering, vaccine drug delivery, polyphosphazene- anticancer drug conjugates with doxorubicin, paclitaxel, platinum complexes, methotrexate and gemcitabine for the targeted drug delivery etc. This review is focused on the recent advances in the biomedical applications of polyphosphazene-drug conjugates.

The chemistry of 1,3,4-thiadiazoles is very well known. A universal and commonly used method of the synthesis of different 2,5-disubstituted 1,3,4-thiadiazoles includes the cyclization of appropriate linear organic derivatives. They are widely known as compounds with various kinds of biological activities showing anticancer properties against human cancers and acting as diuretic, antibacterial, antifungal, antitubercular and leishmanicidal agents. Many of them influence on OUN exhibiting anticonvulsant, anti-inflammatory, antidepressant, analgesic and anxiolytic effects. The molecular target of 1,3,4-thiadiazoles includes the following enzymes: carbonic anhydrase (CA), cyclooxygenase (CO), neutral endopeptidase (NEP), aminopeptidase N (APN), matrix metalloproteinases (MMPs), phosphodiesterases (PDEs) and c-Src/Abl tyrosine kinase. In this presentation, recent achievements in the medicinal chemistry of 1,3,4-thiadiazole based compounds are reviewed.

Oxidative stress plays an important role in both initiation and progression of neurodegenerative diseases, such as Alzheimer and Parkinson. Therefore, much attention has been paid to antioxidants for developing therapeutic strategies for the neurodegenerative diseases. However, as serious adverse effects are related to synthetic antioxidants, recent research has been focused on natural products especially phenolic antioxidants. In the present article, we critically review the available literature related to the beneficial role of ferulic acid on Alzheimer’s disease, since it is a natural antioxidant which is widely found in different fruits and vegetables. We also provide some informations about sources, chemical structure, bioavailability and clinical impacts of ferulic acid.

Nowadays, heterocyclic compounds which have a nitrogen atom on the structure, such as pharmacological products, pesticides and antimicrobials can be demonstrated by biologically-active groups that serve the pharmaceutical industry and they are still important in this field. Various cyclization reactions form the basis of the literature on the syntheses of heterocyclic compounds. NArylpiperazines are a class of heterocyclic compounds that play an important role in organic synthesis and are generally found as fragments in receptor ligands and natural products. They have been used extensively as reactive species for building chemical diversity. Arylpiperazines are also found in many pharmacologically-active molecules. Our research group has published numerous papers over the last two years on the synthesis of potentially bioactive tandospirone analogues which have a piperazine group by reductive Heck reactions. We also reported some important isoxazoline derivatives by 1,3-dipolar cycloadditions. Our work continued with potentially pharmacologically-active tandospirone analogues which have an exo-ring in the tricyclic system with an oxygen bridge and containing a 3-(trifluoromethyl)phenyl and 2,3-dichlorophenyl group on the aromatic ring.