ChemInform Abstract: A Remarkably Simple One‐Step Procedure for the Preparation of α‐Bromo‐α,β‐Unsaturated Carbonyl Compounds

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option

4-[2-(Trimethylsilyl) Ethynyl]Benzoates: Synthesis and Evaluation for Mesomorphic Properties of some Novel Calamitic Molecules

A series of novel terminal trimethylsilylacetylene benzoate derivatives with various linking groups were synthesized using Friedel-Craft's O-acylation reaction. The chemical structures of the novel4-[2-(trimethylsilyl)ethynyl]benzoates were confirmed by standard spectroscopic techniques. The compounds were investigated for their liquid crystalline properties employing polarised optical microscopy and differential scanning calorimetry. The esters 5c – 5f, 5h and 5n possessing three phenyl rings exhibited liquid crystalline property of SmA/SmC phases with wide thermal range

Symmetric 3,5-Pyrazole and Isoxazole Heterocycles Comprising a Bent Core Unit: Synthesis and Mesomorphic Characterisation

The synthesis and characterisation of some new liquid crystalline (LC) heteroaromatic compounds containing the five-membered pyrazole/isoxazole rings is reported. Some of the compounds exhibited enantiotropic LC properties. The transition temperatures and LC textures of the mesophases were determined using polarised optical microscopy (POM), differential scanning calorimetry (DSC) and X-ray studies. The five-membered heterocyclic compounds with the pyrazole core exhibit smectic C (SmC) phase, whereas isoxazoles show SmC and nematic (N) phases

Clinical study on complicated presentations of groin hernias

Background: Groin hernia is a very common type abdominal wall hernia encountered in surgical practice. Irreducibility, obstruction and strangulation are its commonest complications which usually presents as acute emergencies. Emergency repair of complicated hernias is associated with poor prognosis and a high rate of post-operative complications even with better care, improved anaesthetic management and advanced surgical techniques. The aim of this study was to determine the various modes of presentation, clinical finding, diagnostic and therapeutic strategies and to evaluate the postoperative outcome in complicated groin hernia surgeries in our set up.Methods: The study was carried out among 40 patients of groin hernia, who had complicated clinical presentation like irreducibility, strangulation and obstruction in the department of general surgery, during the period from March 2012 to June 2014. Patients were enrolled into the study after proper consent for detailed clinical examination, investigation and subsequent treatment. The Data obtained included demographic characteristics, presentation, operative findings and outcome. The patients were followed up for immediate and late complications for once a week for 1 months, once every month for the next 6 months. After data collection, analysis was done with help of by SPSS software version 21.Results: A total of 40 groin hernia patients with complicated presentation were evaluated during the study period. Among these cases 38 cases had inguinal hernias and two cases had femoral hernia. Majority of the patients were in 5th and 6th decade. Complicated presentation of groin hernia was commonly seen in males (95%) than in females (5%) with male to female ratio of 19:1. Inguinal hernia complications were seen predominantly in males and femoral hernia complications in females. Right sided hernias were more common. Incarceration was the commonest complication seen in 70% of case followed by strangulation (30%). Incarceration was high (17.5%) in the age group of 64-73 years and 44 - 53 years. Strangulation was high in the age group of 54-63 years. The duration of hernia varied for 1-2 years in 42.5% of cases and 3-6 years in 27.5% of cases. Majority of the patients (30%) presented with localized groin pain, vomiting, constipation and abdominal distension. All patients presented with swelling in the inguinoscrotal region, which was tender, and there was no impulse on coughing and 35% of patients had cardiorespiratory illness. Majority of the cases (34 numbers) were operated as emergency procedure. Viable bowel was seen in 77.5% of cases. Bowel resection and end-to-end anastomosis was done in all cases of non-viable bowel and orchidectomy in atrophied and gangrenous testis. The commonest postoperative complication encountered in the study was wound infection (22.5%) and scrotal seroma (17.50%). There was no evidence of recurrence in any of the operated cases.Conclusions: Complicated presentations of groin hernias like, incarceration and strangulation are seen in low and middle socio-economic category of people and may be associated with chronic illness. The cumulative risk of strangulation increases with time and type of hernias. Timely diagnosis and prompted surgical repair is essential to prevent the complications.

Synthesis of some Novel Aromatic Alkynyl Silanes: Mesomorphic Characterization of Ethynyl-Substituted Rod-Shaped Molecules

The synthesis and characterization of 10 new rod-shaped substituted benzoates possessing the 4-(2-trimethylsilyl)ethynyl group in terminal phenyl position is reported employing the simple and efficient Sonogashira cross-coupling and DCC esterification. 4′-Dodecylbiphenyl-4-carboxylic(2-trimethylsilylethynyl)-phenyl ester (3i), 4-(4′-hexadecyloxybenzyloxy) carboxylic-4-trimethylsilanylethynyl-phenyl ester (3j), and 1,4-bis(4-(pentyloxy)phenyl)buta-1,3-diyne (7) compounds were evaluated for liquid crystal property

Granulomatous dermatosis: histopathological study in a tertiary care hospital

Background: Granulomatous dermatosis shares the histological finding of granuloma formation; it is usually formed because of the persistence of a non-degradable product of active hypersensitivity. The identical histological picture may be produced by several causes, which pose a diagnostic challenge to dermatopathologist, Present study aims at classifying cutaneous granulomatous dermatosis based on the morphology and aetiology of granulomas, and to highlight its significance for specific clinical diagnosis.Methods: A retrospective analysis of skin biopsy was done and cases of cutaneous granulomatous lesions diagnosed on histopathological examination were retrieved for a period of 8 years. Clinical data and diagnosis were retrieved from hospital records. Hematoxylin and eosin stained paraffin sections were reviewed. The morphological pattern of granuloma was classified into sarcoidal, necrotizing, necrobiotic and suppurative granulomas and further aetiological evaluation for the granulomatous dermatosis were done using various special stains like Periodic Acid Schiff stain, Fite-Farraco stain, Gomori methenamine silver stain and acid-fast bacilli stain.Results: A total of 228 cases of cutaneous granulomatous lesion were retrieved; out of these 93cases (40.79%) were sarcoidal granuloma type, 83cases (36.40%) were of suppurative granulomas, 29 cases (12.72%) were of necrobiotic granulomas, 20 cases (8.77%) were necrotizing granuloma and 3 cases (1.32%) had granulomatous dermatitis with vasculitis. Infective aetiology was the commonest cause for granulomatous dermatosis (57.89%), mainly by leprosy, tuberculosis and various fungal infection.Conclusions: Granulomatous dermatosis has significant overlap in histopathological picture of various granulomatous reactions. Morphology alone is seldom specific and cannot be used as diagnostic tool. It is better understood based adequate clinical data, morphology of granuloma, special stains and laboratory workup in arriving at a etiology specific diagnosis for definitive clinical management

Sulphuric acid leaching of low/medium grade managanese ores using a novel nitrogeneous reductant-NH3NH2HSO4

Low and medium grade land as well sea based manganese ores were used for manganese extraction in H2SO4 - NH3NH2HSO4 (hydrazine sulphate) medium For land based Mn ores, only Mn recovery is important but for sea nodules which contain substantial amounts Co, Ni, and Cu, their recovery is equally important. In the present studies four samples used were: Indian ocean manganese nodules, medium and low grade Mn ores of Gujarat, and low grade Mn ore of Orissa, India. The Mn content of these ores varied from 15 to 39%. The objective of this work is to establish a reductant which can be used for leaching Mn from all types of ores. The optimum conditions established for nodules by varying parameters such as time, temperature, pulp density, H2SO4 and NH3NH2HSO4 concentrations were: pulp density 10%, time 0.5h, temperature 110ºC, NH3NH2HSO4 3.25 g/10g, H2SO4 2.0% (v/v) for 96.9% Mn, 85.25% Cu, 92.58% Ni and 76.5% Co extractions. More than 92% Mn could be leached from different types of ores by varying amount of reductant and acid concentration at 35ºC. Depending on Mn content 1.0 to 1.2 times stochiometric amount of reductant and 1.5 to 1.8 times sulphuric acid were required for >92% Mn extraction

2DOF PID Controller Design for a Class of FOPTD Models–An Analysis with Heuristic Algorithms

AbstractIn recent years, a number of controller design procedures are developed and implemented in process industries to enhance the performance of closed loop processes. In this paper, heuristic algorithm based Two Degrees Of Freedom (2DOF) PID controller design is proposed for a class of First Order Plus Time Delay (FOPTD) systems existing in the literature. Minimization of the weighted sum of multiple objective functions is considered to monitor the heuristic search towards the optimal controller parameters. A detailed comparative analysis between well known heuristic methods, such as Particle Swarm Optimization (PSO), Bacterial Foraging Optimization (BFO), Cuckoo Search (CS) and Firefly Algorithm (FA) are presented. The popular 2DOF PID structures, such as Feed Back Structure (FBS) and Feed Forward Structure (FFS) are considered in this work to enhance the performance of FOPTD systems. From the results, it is noted that, proposed controller provides enhanced results for the reference tracking and disturbance rejection operations

Antimicrobial activity of Rauvolfia tetraphylla and Physalis minima leaf and callus extracts

The in vitro antimicrobial activity of Rauvolfia tetraphylla and Physalis minima leaf and callus extracts were studied against selected pathogenic fungi and bacteria, following broth dilution assay. Leaves and calli were extracted using absolute alcohol, benzene, chloroform, methanol and petroleum ether. Among the five solvents used, leaf and callus extracted in chloroform of both the plants were found to be more effective against pathogenic bacteria and fungi, where the minimum inhibitory concentration (MIC) ranged between 0.25 to 6 mg/ml. Absolute alcohol extracts showed MIC of 0.25 to 4 mg/ml forbacteria, whereas for fungi it ranged from 0.25 to 100 mg/ml. Extracts of benzene and petroleum ether were ineffective in inhibiting the bacterial and fungal growth or showed poor inhibition. Methanol extract showed MIC of 0.25 to 100 mg/ml against bacterial pathogens and 0.5 to 100 mg/ml againstfungal pathogens. The antimicrobial activities of these two indigenous medicinal plants were discussed in the present pape

Synthesis of 1-Trimethylsilyl-2-Arylcyclohexenes: A New Class of Anionic Synthons

The sequential synthesis of eleven novel 1-trimethysilyl-2-arylcyclohexenes 4a–k from 1-bromo-2-chlorocyclohexene (1) is reported. The Suzuki cross coupling of 1 with eleven aryl boronic acids 2a–k gave the 1-chloro-2-arylcyclohexenes 3a–k in >90% yields. Wurtz–Fittig coupling reaction of 3a–k with metallic sodium and chlorotrimethylsilane in anhydrous ether solvent afforded the novel anionic synthons: 1-trimethylsilyl-2-arylcyclohexenes 4a–k in 65–87% yields. The cyclic vinylsilanes 4a–j are liquids, and 1-trimethylsilyl-2-biphenylcyclohexene (4k) exists as a solid. The crystal structure of 4k is discussed. A plausible mechanism for the Wurtz–Fittig reaction and formation of vinylsilanes is highlighted