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We describe the efficient total syntheses of naturally occurring tripeptides acidiphilamides A–C and epi-acidiphilamides A–C, which were prepared from commercially available l-phenyl alanine using hexafluorophosphate azabenzotriazole tetramethyl uronium (HATU) as peptide coupling reagent. The structures of the natural acidiphilamides A, B and C were characterized by NMR, MS and SOR data, which match those of natural products, whereas the structures of epi-acidiphilamides A, B and C were confirmed by 2D NMR studies.

An efficient and simple synthesis of various 3-(trifluoromethyl)chromones from enamino ketones is described. The key step in the synthesis involves the introduction of a trifluoromethyl (CF3) moiety onto a chromone structure. The significant features of this method include simple operational procedures, the high purity and yield of the product, and excellent regioselectivity.

An efficient and novel method for the preparation of unnatural α-amino acids (UAAs) containing 7-hydroxy-2,2-dimethyl-chroman via a 1,3-di-polar-cyloaddition reaction has been described. Using this method, various new ethyl 2-amino-3-(3-(7-hydroxy-2,2-dimethylchroman-6-yl)isoxazol-5-yl)propanoate derivatives have been prepared where the isoxazole ring is acting as a linker between alanine and chroman moieties. This is the first example of isoxazole-tethered 2,2-dimethylchroman-amino acid hybrids.

A new regioselective method for the synthesis of 2-aryl-5-benzoylpyridine derivatives has been developed. The reaction proceeds via ring opening and closing cascade mechanism (ROCC) of isoxazole to synthesize various functionalized pyridine derivatives. This is the first report for the preparation of 2,5-di-substituted pyridines using Fe/NH4Cl as a reducing reagent. Keywords: Isoxazole, 2,5-Disubstituted pyridines, ROCC mechanism, Fe/NH4Cl

An efficient synthesis of various 3-fluorochromones (3-fluoro-4H-chromene-4-ones) from enamino ketones by using Selectfluor is described. The key step in the synthesis involves tandem fluorination and cyclization to form 3-fluorochromones in good yields. The significant features of this method include simple operational procedures, a high purity of the product, and excellent regioselectivity.

Ag nanoparticles (AgNPs) catalyst material is bio-synthesized and fully examined using various spectroscopy and microscopy techniques. Further this synthesized material is used for hydroxylation reaction, for this purpose we developed a simple and versatile bio-based method from aryl boronic acids to phenol. The reaction was studied in the presence of low cost ligand in a hydrated reaction medium without any hazardous organic solvents, as a result a finite amount of yield was achieved in short time (

A new regioselective method for the synthesis of 3-(methylthio)-4H-chromen-4-one and 3-(phenylthio)-4H-chromen-4-one derivatives has been developed. The reaction between o-hydroxy-phenyl-functionalized enaminones and methylsulfinyl derivatives using T3P® gave good yields of chromone thioether derivatives. The reaction proceeds via domino chromone ring construction and C(sp2)–H bond sulfenylation under transition-metal-free conditions.

Background: Type 2 Diabetes Mellitus (T2DM) is the most prevalent metabolic disorder in the world. Recent evidence however suggests that T2DM is not only a disease of metabolism, but also an inflammatory disorder and that inflammation also plays an important role in the pathogenesis of Diabetic complications. Our aim was to study the level of interleukin-17 (IL 17) in Indian populations with T2DM as an inflammatory marker and analyze its role in different diabetic complications. Methods: A total of consecutive 67 patients of T2DM were evaluated for clinical parameters fasting blood glucose (FBG), 2hr-post-prandial blood glucose (PPBG), lipid profile, HbA1c and plasma IL 17. They were divided into three groups—Patients of T2DM without any complications (group A; n = 24), T2DM with acute complications (group B; n = 20), T2DM with chronic complications (group C; n = 23) and compared with 23 healthy controls (group D). Results: Diabetic patients had a higher level of IL 17 as compared to the healthy controls. The level of IL 17 in complicated diabetics was higher than the patients with T2DM without complications. Multiple logistic regression analysis showed positive correlation of IL 17 with Diabetic Retinopathy and Diabetic Neuropathy. IL 17 also showed a positive Pearsons correlation with systolic blood pressure (SBP), diastolic blood pressure (DBP), serum triglycerides (TG), serum total cholesterol (TC), very low density lipoproteins (VLDL), low density lipoproteins (LDL), HbA1c and a negative correlation with HDL. Conclusion: Indian subjects with T2DM with or without complications had higher values of IL 17 as compared to healthy controls. Also diabetic neuropathy and diabetic retinopathy were positively correlated to levels of IL 17. Further levels of IL 17 were positively correlated to hypertension and dyslipidemia indicating a prevalent inflammatory state in our population of T2DM with and without complications.

Objective: To describe clinical profile and management pattern of headache in patients presenting to a tertiary care center. Methods: In this observational study, demographics, radiological investigations, triggers, and treatment pattern in patients aged ≥ 14 years presenting with headache were recorded. Disability and severity of headache were assessed with Migraine Disability Assessment (MIDAS) score, Visual Analogue Scale (VAS), and Headache Impact Test (HIT-6) in case of migraineurs and VAS and HIT-6 for all other headache disorders. Patients were evaluated at baseline and after three and six months post-treatment. Results: Out of 400 patients (60.25% females and 39.75% males), 277 (69.25%) had primary headache among whom 119 (42.96%) had migraine without aura. Stress, menstruation, fasting, and inadequate sleep were common triggers for migraine. Nausea, vomiting, photo-phonophobia and neck pain were the most common accompanying symptoms in patients with headache. Out of 106 (38.3%) patients with tension-type headache, 68.9% were episodic. In the migraine subset, 81% presented with moderate to severe disability at baseline, which changed to minimal to mild disability at three and six months post-treatment (p < 0.001). For abortive treatment, 130 (79.7%) patients were prescribed naproxen, domperidone, and sumatriptan. In 69 (42.3%) patients, valproic acid/divalproex was used for prophylaxis. Most common causes of secondary headaches (30.75%) were intracranial bleeds and cerebral venous sinus thrombosis. Most common abnormalities on computerized tomography were intracerebral hemorrhage, subarachnoid hemorrhage, sinusitis, and space-occupying lesions (SOLs). Conclusion: In our study, migraine was the most common etiology of headache. Headache was more common in females than males, and primary headache was more common than secondary headache. Sodium valproate was the commonly used prophylaxis in migraine.

The synthesis of N-formamides from aromatic amines and formic acid using propylphosphonic anhydride (T3P®) as a green coupling reagent is described. By using this method, aryl, heteroaryl and fluorinated aryl-containing formamides were synthesized in high yield and purity. The significant features of this method include easy work up, high purity and reduced toxicity of the reaction.

An efficient synthesis of 4H-chromene-4-ones via enamino ketones, with cyclization by using T3P® under microwave heating is described. This is the first report for the synthesis of chromones by using T3P®. Significant features of this method include short reaction times and high-purity products.

An efficient method for the preparation of chromone based $$\upalpha $$ -amino acid derivatives by alkylation of glycinate schiff base with 3-bromomethyl chromone as well as 2-bromomethyl chromone has been described. Using this method, 2-amino-3-(4-oxo-2-chromenyl)propanoic acid and 2-amino-3-(4-oxo-3-chromenyl)propanoic acid, two novel chromone-amino acid conjugates have been prepared. Furthermore, the separation of chromone amino acid enantiomers by chiral column chromatography was accomplished. Synopsis: An efficient method for the preparation of chromone based $$\upalpha $$ -amino acid derivatives by alkylation of glycinate schiff base with 3-bromomethyl chromone as well as 2-bromomethyl chromone has been described. These conjugates can be considered as analogues of phenyl alanine where phenyl group has been replaced by chromone moiety.

The reaction of 1,3,4-oxathiazol-2-one derivative with 2-arylidene-1,3-indandione to furnish novel spiroindene-1,3-dione isothiazoline derivatives by Michael/1,3-dipolar [3+2]-cycloaddition reaction was investigated. The key 1,3-dipolar cycloaddition reaction step was examined in toluene solvent at reflux temperature to obtain mixture of two regioisomers (6a and 6b – 14a and 14b) and single isomers (15–20). The scope of this new reaction was demonstrated with many examples with high reactivity and yields.

A facile and versatile procedure for the synthesis of functionalized novel 2,5-diphenyl-5H-chromeno[4,3-d]pyrimidin-5-ol and (2,4-diphenylpyrimidin-5-yl) (2-hydroxyphenyl) methanone has been described. The key step in the synthesis involves the ANRORC reaction of 3-benzoyl chromones with benzamidines.

Background: Data regarding the prevalence of morbidity and mortality in patients of Type 2 Diabetes Mellitus (T2DM) is scanty in India. Objectives: To determine the prevalence of micro and macro vascular complications, acute metabolic complications, infections, Non Alcoholic Fatty Liver Disease (NAFLD) and cause of mortality in T2DM patients admitted to a tertiary care teaching hospital in Eastern India. Material and Methods: This was a hospital-based prospective study evaluating 150 T2DM patients admitted to a tertiary care institution in Eastern India. Diagnosis of micro and macro vascular complications, infections and NAFLD was made using standard protocols. In case of death, the most probable cause was noted. Results: Out of 150 patients, 14.7% of patients were newly diagnosed T2DM and out of them 41% of patients had vascular complications and 54.5% had infections. Of the total patients, 56% had nephropathy, 20% neuropathy, 17.3% retinopathy, 31.3% CVD, 11.3% CAD, 4.6% acute metabolic complications, 44% infections and 16.6% had NAFLD respectively. Macrovascular events occured earlier than microvascular complications. Multiple logistic regression analysis showed strong association of age, duration of diabetes, serum cholesterol, triglyceride, LDL-C with retinopathy (Regression coefficient β: -0.1086807, 0.4127152, -0.0513393, 0.0146429, 0.0587475; p < 0.05, < 0.001, < 0.05, < 0.05, < 0.05 respectively), while only duration of diabetes was strongly associated with nephropathy and neuropathy (Regression coefficient β: 0.2538751, 0.2261636; p < 0.001 for each). Increasing age was associated with CAD (Regression coefficient β: 0.055392; p < 0.05) and FBG was a risk factor for CVD (Regression coefficient β: 0.0055014; p < 0.05). 18.6% patients died due to diabetes related complications. Cardiovascular (CV)-related deaths (CVD+CAD) were most common cause (51.5%: CVD 36.4%, CAD 15.1%) to be followed by infections (27.3%) and then chronic kidney disease (12.1%). Conclusions: This study highlights the high prevalence of vascular complications and infections in T2DM patients of Eastern India. CV-related deaths were principal causes of death, similar to that in developed world.

A series of novel diaziridinyl quinone thiadiazole hybrids (9a–9j) were synthesized starting from 2-hydroxy-5-methoxybenzoic acid 1 in a 7 step synthetic sequence. The key step in the scheme involves the nitrile sulfide cycloaddition reaction of oxathiazolone 4 with p-tosylcyanide to obtain 1,2,4-thiadiazole derivative 5. We have demonstrated that p-tosyl group of thiadiazole 5 can be displaced with various nitrogen heterocycles to generate unknown 3,5-disubstituted thiadiazole derivatives.

An efficient method for the preparation of N-formyl imide via amidine using propylphosphonic anhydride (T3P®) has been described. Using this method many aryl, hetero aryl, alkyl as well as amino acid imides were synthesized in high yields.

Big Data, collection of huge data sets is a widely used concept in present world. Although being stored and analyzed by Cloud services, it poses the greatest challenge of security threats, occurring in the exposure of enormous amount of data. This paper we are going to explain recent security risks, threats, and vulnerabilities with respect to Cloud Services, Big Data [with extra focus on EnCoRe system], Hadoop [with extra focus on HDFS] and throws light on issues dealing with big data analytics. It prominently makes use of recently developed approach called sticky policies and the existing security framework to improve security. This paper provides a literature review on security threats and privacy issues of big data, Hadoop concurrent processing. It also uses Verizon and Twilio which is familiar for its trustworthy implementation of the Hadoop using Amazon Simple Storage services (S3 services).

A new series of isoxazole tethered quinone-amino acid hybrids has been designed and synthesized involving 1,3-dipolar cycloaddition reaction followed by an oxidation reaction using cerium ammonium nitrate (CAN). Using this method, for the first time various isoxazole tethered quinone-phenyl alanine and quinone-alanine hybrids were synthesized from simple commercially available 4-bromobenzyl bromide, propargyl bromide, and 2,5-dimethoxybenzaldehyde in good yield.

A new synthesis of pyrazolo[4,3-d]pyrimidines and isoxazolo[4,5-d]pyrimidines is described. Key steps in the synthesis involve Stille coupling of 4,6-dichloro-2-phenyl-pyrimidine with tributyl(1-ethoxyvinyl)stannane and tandem Schiff-base formation/heterocyclization of 2,6-di-aryl-5-fluoro-4-acetylpyrimidine with hydrazines or ­hydroxylamine to give pyrazolo[4,3-d]pyrimidines and isoxazolo[4,5-d]pyrimidines, respectively. The position of the fluoro group in the ­pyrimidine ring is important for the success of heterocylization reaction.

An efficient method for the preparation of N-formyl imide via amidine using propylphosphonic anhydride (T3P®) has been described. Using this method many aryl, hetero aryl, alkyl as well as amino acid imides were synthesized in high yields.

An efficient method for the preparation of novel 2-(5-arylisoxazol-3-yl)cyclohexa-2,5-diene-1,4-dione hybrids via 1,3-dipolar cycloaddition followed by an oxidation reaction using ceric ammonium nitrate (CAN) has been described. Using this method, various aryl as well as alkyl substituted isoxazole-benzoquinone hybrids were synthesized in high yields.

An efficient method for the preparation of kojic acid based α-amino acid derivatives by alkylation of glycinate schiff base with bromokojic acids have been described. Using this method, mono as well as di alkylated kojic acid-amino acid conjugates have been prepared. This is the first synthesis of C-linked kojic acid-amino acid conjugate where kojic acid is directly linked to amino acid through a C-C bond.

The Pd-catalyzed cross-coupling reaction of aromatic iodides and bromides with allylboronic acid esters (2a,b) in the presence of CsF gave allylated aromatics.

The title compounds, C15H14NO3S2 (I) and C15H15Br2NO3S2 (II), are derivatives of Aib (α-aminoisobutyric acid) with thiophene rings substituted at the Cα position. The Cα substitution causes the backbone to assume an extended conformation in the crystal structure. N–H and C–H donors share the thiophene ring π system for X–H...π interactions. The packings of the molecules are stabilized by intermolecular N–H...O, C–H...O, C–H...π and C–H...Br hydrogen bonds. Br...O interactions and a weak dihydrogen bond have also been observed in the crystal structure of II. The packing adopted by II has maximized the number of interactions that are possible., © Elsevier

An efficient method for the synthesis of mono α-aryl derivatives of diethyl malonate and ethyl cyanoacetate using ethyl-1-imidazole carbamate (EImC) has been described. Using this method many sterically hindered and highly substituted mono α-aryl derivatives of diethyl malonate and ethyl cyanoacetate were synthesized in high yield.

Background: Dyslipidemia is an independent modifiable risk factor for coronary artery disease. Patients with systemic lupus erythematosus (SLE) have dyslipidemia and accelerated atherosclerosis; however, there is paucity of published data on the lipid profile in patients with SLE in Eastern India. This study was done to assess the prevalence and abnormality of lipid profile in patients with SLE admitted to a tertiary care teaching hospital in Eastern India.Methods: This was a hospital based prospective study evaluating SLE patients admitted to a tertiary care institution in Eastern India. 101 patients with SLE admitted consecutively and 100 age and sex matched controls were enrolled for study. Fasting total cholesterol (TC), triglycerides (TG), high density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C) were measured in plasma whereas very low-density lipoprotein cholesterol (VLDL-C) was calculated. Statistical analysis was done using the standard statistical techniques.Results: Out of 101 patients of SLE, 97 were female and 4 were of male gender. The age of the patients ranged from 15 to 47 years with a mean of 27.17 (±8.4) years. Dyslipidemia was found in 58(57.4%) patients. Hypercholesterolemia was found in 23 (22.7%), hypertriglyceridemia in 55 (54.4%), raised LDL-C in 24 (23.7%) cases. Raised TC, TG, and LDL-C was found in 18 (17.8%), and raised TC, TG, LDL-C and low HDL-C was found in 9 (8.9%) cases. There was significant increase in serum cholesterol, triglyceride and VLDL-C while decrease in HDL-C in SLE patients than controls (p

The title compounds, C 19 H 19 I 2 NO 3 and C 19 H 19 Br 2 NO 3 , are derivatives of α-amino­isobutyric acid with halogen substituents at the para and meta positions, respectively. The ethoxycarbonyl and formamide side chains attached to the C α atom of the mol­ecule adopt extended and folded conformations, respectively. The crystal structures are stabilized by N-H···O, C-H···O, C-Br···O and C-I···O interactions.

1,3-Dipolar cycloaddition of nitrile oxides derived from oximes of type (I) with terminal alkynes and following oxidative demethylation offers a regioselective synthesis of isoxazole substituted p-benzoquinones (IV) (10 examples).

A simple approach to the title compounds, which are required as synthons of heterocycles, becomes possible by treatment of arylacetic esters (II) and nitriles (IV) with reagent (I).

The current study was aimed to ascertain presence and severity of coronary artery lesions in patients of Type 2 diabetic mellitus (DM) with coronary artery disease (CAD), in our population, by using scoring system analysis of the coronary angiography.147 consecutive patients with Type 2 DM of chronic stable angina (CSA) were enrolled in the study with 147 age- and sex-matched patients of CSA who did not have diabetes to serve as control. All of them underwent coronary angiography and were evaluated by using four scores to quantify the coronary artery lesions. The scores analyzed were coronary score, extent score, severity score, and atherosclerosis score. Other major risk factors such as smoking and hypertension lipid profile were also evaluated.Type 2 diabetics with CAD had higher coronary score (0.91 +/- 0.63 in diabetics vs. 0.43 +/- 0.39, p0.001), extent score (4.91 +/- 3.1 vs. 2.3 +/- 1.8, p0.001), severity score (1.85 +/- 0.41 vs. 1.2 +/- 0.32, p0.001), and atherosclerosis score (0.52 +/- 0.31 vs. 0.21 +/- 0.26, p0.001) as compared to non-diabetics with CAD. Left main stem involvement, 2-vessel disease, and 3-vessel disease were also more frequent in the diabetics. These diabetes also had higher incidence of obesity, hypertension, and dyslipidemia.In our population, diabetics suffer from higher prevalence of diffuse and extensive coronary atherosclerosis. The grades of stenosis in coronary arteries are also higher in diabetic patients when compared with non-diabetics with CAD, as was the prevalence of other components of the metabolic syndrome.