Synthetic Chemistry

In the present work, some new imidazole derivatives (3i-xii) were synthesized as per design synthetic protocol scheme. The structures of newly prepared compounds were confirmed by modern analytical technique (IR, 1 H-NMR, Mass spectral data) and elemental analysis, results found in full agreement with their assigned structures. All the synthetic compounds were screened for their antimicrobial activity against bacterial strains viz. Escherichia coli (E. coli, MTCC 2961), Staphylococcus aureus (S. aureus, MTCC 3160), Bacillus subtilis (B. subtilis, MTCC 121), Klebsiella pneumoniae (K. pneumoniae, MTCC 3040) and Micrococcus luteus (M. luteus, MTCC 7527)) and fungal strains viz. Candida albicans (C. albicans, MTCC 227), Aspergillus niger (A. niger, MTCC 277) and Aspergillus flavus (A. flavus, MTCC 418); results showed good to remarkable activity. The MIC (minimum inhibitory concentration) values were determined by comparison to ciprofloxacin (anti-bacterial) and fluconazole (anti-fungal) as standard drug. Among them, compound 3iv and 3x exhibited notable antimicrobial activity.

Pyrazolines are well known and important nitrogen containing 5-membered heterocyclic compounds and various methods have been worked out for their synthesis. Numerous pyrazoline derivatives have been found to possess considerable biological activities, which stimulated the research activity in this field. They have several prominent effects, such as antimicrobial, antimycobacterial, antifungal, antiamoebic, anti-inflammatory, analgesic, antidepressant and anticancer activities. They also possess some potent receptor selective biological activity like Nitric oxide synthase (NOS) inhibitor and Cannabinoid CB1 receptor antagonists activity. 4,5-dihydro-1H-pyrazolines seem to be the most frequently studied pyrazoline type compounds. As a result, a large number of such pyrazolines using different synthetic methods for their preparation have been described in the chemistry literature. The present review provides an insight view to pyrazolines synthesis and its biological activities along with the compilation of recent patents on pyrazolines.

Taking the Modern with the Traditional: Introducing the
Challenges of Acrylic Emulsion Painted Banners

Textile Conservator, People’s History Museum, Manchester
Introduction The People’s History Museum (PHM) holds a large collection of traditional oil-based painted banners, such as trade union banners, which are predominately on silk textile grounds. It is perhaps this aspect of the PHM collection that is more commonly known. The museum also holds a good number of banners, flags and other flat textiles which are painted with modern paints, such as
household, industrial and acrylic-based paint media. These banners represent much of the modern facet of the collection and they range from the mid twentieth to the twenty first century and this proportion of banners is expected to increase in the future. The use of modern paints such as, acrylic emulsion paint, have become increasingly popular with artists over the last sixty years
because of their versatile properties. Some of the reasons these synthetic paints have become so popular since the 1960s is because they offer great clarity, phenomenal elasticity and can be painted directly onto supports (Jablonski et al. 2004); properties modern banner makers would find very beneficial. The last decade has seen a significant rise in conservation literature regarding the issues in treating modern paints, specifically relating to contemporary and modern art. A vast amount of work has been done into investigating the characteristics and properties of modern paints, as well as trying to determine the effects of the environment and treatments. This research continues and is primarily lead by institutions such as Tate, London, UK and the Getty
Conservation Institute, Los Angeles, USA

A simple, sensitive, selective, precise, and robust high-performance TLC (HPTLC) method was developed and validated for determination of flavonoids in herbal extracts Bauhinia variegata, Bacopa monnieri, Centella asiatica, Ginkgo biloba, Lonicera japonica, Rosa bourboniana, Rosa brunonii, and Rosa damascena. The HPTLC of flavonoids was performed on RP-18 F254 TLC plates with dual run, water (5% formic acid)/methanol (70:30) and water (5% formic acid)/methanol (50:50) as mobile phases. Densitometric determination of flavonoids was performed at λ = 280 nm in reflectance/absorbance mode. The linear regression analysis data for the calibration plots showed a good linear relationship with r2 = 0.998 ± 0.0003 in the concentration range of 150–800 ng/spot for apigenin and rutin and 200–1000 ng/spot for quercetin, luteolin, and quercitrin with respect to peak area. The average recovery for apigenin, quercetin, rutin, luteolin, and quercitrin was 97–99.8% indicating the excellent reproducibility. Statistical analysis of the data showed that the method is reproducible and selective for determination of flavonoids.

We synthesized the five compounds of azo bridged ethoxybenzothiazole substituted phenyl ester derivatives by using
Dicyclo Hexyl Carbodiimide (DCC) and a catalytic amount of Dimethyl amino pyridine (DMAP) as a nucleophile. All
the compounds structures were confirmed by IR, NMR and mass spectrum. The synthesized compounds were screened for
antioxidant property by DPPH radical scavenging method. (E)-4-[(6-ethoxy benzothiazol-2-yl) diazenyl] phenyl 2-methyl
benzoate (B1) and (E)-4-[(6-ethoxy benzothiazol-2-yl) diazeny]) phenyl 4-fluoro benzoate (B5) showed comparable
activities.

This protocol provides a detailed procedure for the preparation of stapled α-helical peptides, which have proven their potential as useful molecular probes and as next-generation therapeutics. Two crucial features of this protocol are (i) the construction of peptide substrates containing hindered α-methyl, α-alkenyl amino acids and (ii) the ring-closing olefin metathesis (RCM) of the resulting resin-bound peptide substrates. The stapling systems described in this protocol, namely bridging one or two turns of an α-helix, are highly adaptable to most peptide sequences, resulting in favorable RCM kinetics, helix stabilization and promotion of cellular uptake.

In the 2010s, synthetic marijuana products, mostly referred to as Bonzai, have become a critical phenomenon in the drugs realm worldwide. In Turkey and many other countries, state authorities and the public have been alarmed about the rapid widespread of these drugs. Frequent cases of death related to Bonzai use have placed these substances among the top concerns on the public’s agenda. This article primarily aims to analyze the conditions and factors that have enabled Bonzai’s rapid popularization among Turkish drug users. To achieve this, I have used a compilation of qualitative data received from books, articles, news sources, expert comments, official drug reports and interviews with five male ex-users living in Istanbul. From this data, certain factors contributing to the increasing popularity of Bonzai drugs in Turkey have been deduced. Furthermore, significant information related to these substances’ history and the causes of death cases in Turkey have been noted from the interviewees.

Addicta: The Turkish Journal on Addictions, Spring 2014, 1(1), pp.41-62, DOI: 10.15805/addicta.2014.1.1.011

Despite the multidisciplinary dimension of the researches conducted under the umbrella synthetic biology, the founders of this new research area in the United States adopted a disciplinary profile to shape its institutional identity. In so doing they took inspiration from two already established fields with very different disciplinary patterns. The analogy with synthetic chemistry suggested by the term 'synthetic biology' is not the unique model. Information technology is clearly another source of inspiration. The purpose of the paper focused on the US context is to emphasize the diversity of views and agendas coexisting under the disciplinary label synthetic biology, as the two models analysed are only presented as two extreme postures in the community. The paper discusses the question: in which directions the two models shape this emerging field? Do they chart two divergent futures for synthetic biology?

In the current study, a-aminophosphonates containing thiadiazole moiety (1-4) was synthesized , characterized and their antioxidant and anticancer activities were carried out. The compounds (1-4) were synthesized from the reaction of 2-amino-5-methyl-1,3,4-thiadiazole with various aldehydes, triphenylphosphite and mixed valence Cu(I)/Cu(II) inorganic coordination polymer as a catalyst. The elucidation of compounds structures were carried out using different spectro-scopic techniques. The antioxidant properties were carried out using radical scavenging methods (DPPH) which exhibited excellent scavenging activity particularly with compound 3. The cytotoxic effects of the five compounds on the human hepato cellular carcinoma (HepG2) and breast adeno carcinoma (MCF7) cell lines were evaluated using MTT assay which revealed the presence of cyto-toxic effect with highest activity for compound 3 on HepG2 and compound 1 on MCF7. This suggests that these five compounds, particularly compounds 1 and 3, have antioxidant and anticancer effect and could be used as novel chemotherapeutic compounds but this needs further in vivo investigation to confirm our in vitro results. Ó 2017 King Saud University. Production and hosting by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Drug-induced photosensitivity of the skin is drawing increasing attention. In past few decades, photosensitivity has been reported with an array of drugs, and is now recognized as a noteworthy medical problem by clinicians, regulatory authorities and pharmaceutical industry. The photosensitivity is of two types i.e., phototoxicity and photoallergy. Phototoxic disorders have a high incidence, whereas photoallergic reactions are much less frequent in human population. Several hundred substances, chemicals, or drugs may invoke phototoxic and photoallergic reactions. In order to avoid photosensitive reactions, it is essential to understand the mechanism behind the photosensitizing properties of such substances before these drugs are introduced in clinical settings. Photosensitization is interrelated to photochemical reaction, through the knowledge of which the photosensitivity of a drug can be anticipated. This review highlights the current research status on photosensitizing drugs and its correlation to phototoxicity. Different mechanisms of photodegradation of pho-tolabile drugs have also been discussed.

Herein, we report the synthesis of DNA-functional-ized infinite-coordination-polymer (ICP) nanoparticles as biocompatible gene-regulation agents. ICP nanoparticles were synthesized from ferric nitrate and a ditopic 3-hydroxy-4-pyridinone (HOPO) ligand bearing a pendant azide. Addition of Fe III to a solution of the ligand produced nanoparticles, which were colloidally unstable in the presence of salts. Conjugation of DNA to the Fe III –HOPO ICP particles by copper-free click chemistry afforded colloidally stable nucleic-acid nanoconstructs. The DNA–ICP particles, when cross-linked through sequence-specific hybridization, exhibited narrow, highly cooperative melting transitions consistent with dense DNA surface loading. The ability of the DNA–ICP particles to enter cells and alter protein expression was also evaluated. Our results indicate that these novel particles carry nucleic acids into mammalian cells without the need for transfection agents and are capable of efficient gene knock-down.

Application of microfluidics to Positron Emission Tomography (PET) tracer synthesis has attracted increasing interest within the last decade. The technical advantages of microfluidics, in particular the high surface to volume ratio and resulting fast thermal heating and cooling rates of reagents can lead to reduced reaction times, increased synthesis yields and reduced by-products. In addition automated reaction optimization, reduced consumption of expensive reagents and a path towards a reduced system footprint have been successfully demonstrated. The processing of radioactivity levels required for routine production, use of microfluidic-produced PET tracer doses in preclinical and clinical imaging as well as feasibility studies on autoradiolytic decomposition have all given promising results. However, the number of microfluidic synthesizers utilized for commercial routine production of PET tracers is very limited. This study reviews the state

Recent experiments have shown that supercritical water (SCW) has the ability to accelerate and make selective synthetic organic reactions, thus replacing the common but environmentally harmful acid and basic catalysts. In an attempt to understand the intimate mechanism behind this observation, we analyze, via first-principles molecular dynamics, the Beckmann rearrangement of cyclohexanone oxime into ε-caprolactam in supercritical water, for which accurate experimental evidence has been reported. Differences in the wetting of the hydrophilic parts of the solute, enhanced by SCW, and the disrupted hydrogen bond network are shown to be crucial in triggering the reaction and in making it selective. Furthermore, the enhanced concentrations of H+ in SCW play an important role in starting the reaction.

... Phone: +61 3 990 39000, Fax: +61 3 99039582, e-mail: [email protected], http://synapse.vcp.monash.edu.au/martin/ Received: 27 February 1998 / Published: 6 March 1998 The general part of the experimental section [1] has been presented elsewhere. ...

Pyrazolines are well known and important nitrogen containing 5-membered heterocyclic compounds and various methods have been worked out for their synthesis. Numerous pyrazoline derivatives have been found to possess considerable biological activities, which stimulated the research activity in this field. They have several prominent effects, such as antimicrobial, antimycobacterial, antifungal, antiamoebic, anti-inflammatory, analgesic, antidepressant and anticancer activities. They also possess some potent receptor selective biological activity like Nitric oxide synthase (NOS) inhibitor and Cannabinoid CB1 receptor antagonists activity. 4,5-dihydro-1H- pyrazolines seem to be the most frequently studied pyrazoline type compounds. As a result, a large number of such pyrazolines using different synthetic methods for their preparation have been described in the chemistry literature. The present review provides an insight view to pyrazolines synthesis and its biological activities along with the compilation of recent patents on pyrazolines.

Solids of the stoichiometric formulae [Fe{S2P(OPr-n)2}3] and [Fe{S2PO2G}3] (G = —CH2CMe2CH2—, CMe2−CMe2— or —CH2CH2CHMe—) are precipitated from the reactions of FeCl3 with ammonium dithiophosphates in water. Soluble complexes of the type [Fe{S2PO2G}2], formed by the reactions of FeCl2 with NH4[{S2PO2G}] in MeOH, can be extracted with benzene. Adducts of the types [Fe{S2PO2G}2L] and [Fe{S2PO2G}2(PPh3)2] are formed by the reaction of [Fe{S2PO2G}2] with L (L = 2,2′-bipyridyl or 1,10-phenanthroline) and PPh3, respectively. All the compounds have been characterized by i.r. and u.v.-vis. spectroscopy and magnetic studies.