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Calcium manganites (CaMnO3) ceramic powders were prepared by sol–gel technique using citric acid as a chelating agent. The polycrystalline powder crystallized in an orthorhombic structure with lattice parameters a = 5.270 A, b = 7.421 A and c = 5.231 A. Dielectric relaxation was observed which can be attributed to Maxwell–Wagner relaxation behavior. The oxidation states of Calcium, Manganese and the presence of oxygen deficiencies in the prepared samples were ascertained by XPS studies.

It has always been a challenge to develop interventional therapies for

In the present study, we have discussed about the synthesis of Ca0.9Dy0.1MnO3 by using citric acid as a chelating agent. Structural and morphological studies were carried out by using XRD, FT-IR, FE-SEM equipped with EDX for the synthesized material. Magnetic studies are carried out by VSM and confirmed the paramagnetic behavior. The electric properties like dielectric, impedance and conductivity is carried out at the frequency range of 50 Hz to 5 MHz for different temperatures. Impedances studied for the activation energy and the investigation of grain and grain boundary effects. The conductivity studies were explained on the basis of Jonscher's power law and the activation energy is calculated. Keywords: Sol–gel, Structural, Dielectric properties, Electrical properties, Impedance spectroscopy

Molecular Simulations Group, Department of Pharmaceutical Chemistry, Bombay College of Pharmacy, Kalina, Santacruz East, Mumbai-400 098, India Aix-Marseille Univ, CNRS, AFMB UMR 7257, Marseille, France Ambernath Organics Pvt. Ltd., 222, The Summit Business Bay, Andheri (E), Mumbai-400 093, India E-mail: evans.coutinho@bcp.edu.in, santosh.nandan@ambernathorganic.com Manuscript received online 30 June 2020, accepted 20 July 2020 Various studies have shown that NS5 RNA methyltransferase (MTase) is a key enzyme involved in mRNA capping, a step crucial for flaviviral replication. Therefore, it has been identified as a potential target for therapeutic intervention in infections arising due to flaviviruses. In this paper, we report computer-assisted design of 2,3-dioxopyrrolidines, which were synthesised as guided by molecular docking studies on DENV and ZIKA MTase. Their chemical structures and geometric configuration were characterized by FT-IR, NMR (13C and 1H), MS and small molecule X-ray crystallography. Subsequently, their inhibitory potential was evaluated using an enzyme-based assay in DENV MTase (N7 and 2'O-MTase) and Zika virus MTase (N7 and 2'O-MTase). Furthermore, these molecules were also screened against RNMT (human N7 MTase). The most potent lead (compound W07) is seen to inhibit MTase from DENV with IC50 = 24.6±3.8 µM and ZIKA with IC50 = 9.0±1.7 µM. However, it also inhibits human N7 MTase, indicating plausible toxicity in humans. There is scope to further optimize these molecules to achieve selectivity towards flaviviral MTases.

Background The emergency surgery score is a mortality-risk calculator for emergency general operation patients. We sought to examine whether the emergency surgery score predicts 30-day morbidity and mortality in a high-risk group of patients undergoing emergent laparotomy. Methods Using the 2011–2012 American College of Surgeons National Surgical Quality Improvement Program database, we identified all patients who underwent emergent laparotomy using (1) the American College of Surgeons National Surgical Quality Improvement Program definition of “emergent,” and (2) all Current Procedural Terminology codes denoting a laparotomy, excluding aortic aneurysm rupture. Multivariable logistic regression analyses were performed to measure the correlation (c-statistic) between the emergency surgery score and (1) 30-day mortality, and (2) 30-day morbidity after emergent laparotomy. As sensitivity analyses, the correlation between the emergency surgery score and 30-day mortality was also evaluated in prespecified subgroups based on Current Procedural Terminology codes. Results A total of 26,410 emergent laparotomy patients were included. Thirty-day mortality and morbidity were 10.2% and 43.8%, respectively. The emergency surgery score correlated well with mortality (c-statistic = 0.84); scores of 1, 11, and 22 correlated with mortalities of 0.4%, 39%, and 100%, respectively. Similarly, the emergency surgery score correlated well with morbidity (c-statistic = 0.74); scores of 0, 7, and 11 correlated with complication rates of 13%, 58%, and 79%, respectively. The morbidity rates plateaued for scores higher than 11. Sensitivity analyses demonstrated that the emergency surgery score effectively predicts mortality in patients undergoing emergent (1) splenic, (2) gastroduodenal, (3) intestinal, (4) hepatobiliary, or (5) incarcerated ventral hernia operation. Conclusion The emergency surgery score accurately predicts outcomes in all types of emergent laparotomy patients and may prove valuable as a bedside decision-making tool for patient and family counseling, as well as for adequate risk-adjustment in emergent laparotomy quality benchmarking efforts.

Background The Emergency Surgery Score (ESS) was recently validated as a scoring system to predict mortality in emergency surgery (ES) patients. We sought to examine the ability of ESS to predict the occurrence of 30-day postoperative complications in ES. Methods The 2011-2012 American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database was screened for all surgical operations classified as "emergent." Thirty-day postoperative complications were defined as per ACS-NSQIP (e.g., surgical site infection, respiratory failure, acute renal failure). Each patient-related ESS was calculated, and the correlation between ESS and the probability of occurrence of 30-day postoperative complications was assessed by calculating the c-statistic. Univariate and multivariable models were also created to identify which ESS components independently predict complications. Results Of 37,999 cases that captured all ESS variables, 14,446 (38%) resulted in at least one 30-day complication. The observed probability of a 30-day complication gradually increased from 7% to 53% to 91% at scores of 0, 7, and 15, respectively, with a c-statistic of 0.78. For ESS >15, the complication rate plateaued at a mean of 92%. On multivariable analyses, each of the 22 ESS components independently predicted the occurrence of postoperative complications. Conclusions ESS reliably predicts postoperative complications in ES patients. Such a score could prove useful for (1) perioperative patient and family counseling and (2) benchmarking the quality of ES care. Level of evidence Prognostic, level III.

Background An intraoperative adverse event (iAE) is often directly attributable to the surgeon's technical error and/or suboptimal intraoperative judgment. We aimed to examine the psychological impact of iAEs on surgeons as well as the surgeons' attitude about iAE reporting. Study Design We conducted a web-based cross-sectional survey of all surgeons at 3 major teaching hospitals of the same university. The 29-item questionnaire was developed using a systematic closed and open approach focused on assessing the surgeons' personal account of iAE incidence, emotional response to iAEs, available support systems, and perspective about the barriers to iAE reporting. Results The response rate was 44.8% (n = 126). Mean age of respondents was 49 years, 77% were male, and 83% performed >150 procedures/year. During the last year, 32% recalled 1 iAE, 39% recalled 2 to 5 iAEs, and 9% recalled >6 iAEs. The emotional toll of iAEs was significant, with 84% of respondents reporting a combination of anxiety (66%), guilt (60%), sadness (52%), shame/embarrassment (42%), and anger (29%). Colleagues constituted the most helpful support system (42%) rather than friends or family; a few surgeons needed psychological therapy/counseling. As for reporting, 26% preferred not to see their individual iAE rates, and 38% wanted it reported in comparison with their aggregate colleagues' rate. The most common barriers to reporting iAEs were fear of litigation (50%), lack of a standardized reporting system (49%), and absence of a clear iAE definition (48%). Conclusions Intraoperative AEs occur often, have a significant negative impact on surgeons' well-being, and barriers to transparency are fear of litigation and absence of a well-defined reporting system. Efforts should be made to support surgeons and standardize reporting when iAEs occur.

The structural and electrical properties of CaMnO3 prepared by a sol-gel technique using citric acid as a chelating agent at 8000C were studied; the phase formation was determined by powderXRD. The surface morphological studies were carried out through SEM and EDX confirmed the chemical compositions of the sample. The various modes of vibrations due to the Mn-O and O-Mn-O stretching bonds were observed by FTIR spectroscopy studies.The electrical properties of the prepared samples were analysed at different temperatures in the frequency ranges from 50Hz to 5MHz.

Nanosized particles of La0.9Dy0.1MnO3 were prepared by sol–gel technique using citric acid as a chelating agent. The compound was analysed by powder X-ray diffraction technique and found to be sing...

(Ba1−xSrxTi0.6Zr0.3Mn0.1O3) x = 0.1 and 0.2 ferroelectric material were synthesized by solid state method. XRD studies confirmed the single phase formation, and the functional group confirmation was done using Fourier transform infrared spectroscopy. Dielectric relaxations were observed at different frequency ranges for different temperatures. Activation energy Ea is calculated using Arrhenius equation from impedance and modulus which corresponds to the existence of oxygen vacancies.

Polycrystalline Ca0.925Ce0.075Mn0.9Fe0.1O3 were prepared by sol-gel reaction at 1073 K. The compound was analyzed by a powder X-ray diffraction technique and found to be in single phase. The unit-cell parameters and atomic positions were refined using General Structure Analysis to an orthorhombic structure with space group Pnma (#62) a = 5.281 90 (33) Å, b = 7.4968 (45) Å, and c = 5.302 90 (32) Å.

Conducting polyaniline (PANI)/vanadium pentoxide (V2O5) nanocomposites have been synthesized by interfacial polymerization technique. The composites have been characterized by X-ray diffraction (XRD), Fourier transforms infrared (FTIR) spectroscopy, and scanning electron microscopy (SEM). The electrical conductivity (σac) and dielectric measurements have been carried out in the frequency range of 50 Hz to 1 MHz at ordinary lab temperature. The dielectric constant of the composites has been increased to a very high-value of 3.75 × 105 at lower frequency (1 kHz) for 15 wt% concentration of V2O5 in PANI. The electromagnetic shielding behavior of the composites has been investigated in the frequency range 12–18 GHz (Ku-band) of the microwave region. The shielding results demonstrate the synergistic effect of the composite phases with average shielding effectiveness (SE) values in the range of ~17 to 19 dB (

In this present study, nanocrystalline perovskite structure CaMnO3 substituted with Ce and Fe was prepared by a sol–gel technique using citric acid as a chelating agent at 800 °C. The compound was analyzed by powder X-ray diffraction technique and found to be single phased orthorhombic perovskite structure with space group Pnma. The morphology of the synthesized material study is carried out by using SEM and EDX confirmed the chemical compositions of the sample. Electrical measurements were performed to determine the conductive nature of the sample, and the conductivity increases with increasing Fe concentration. Electrode polarization effect was apparently seen in the Nyquist plot and the conductivity measurements. Dielectric relaxations were present in the sample was attributed to the existence of oxygen vacancy, migration in the ions and the Ea is calculated using Arrhenius equation.

Purpose: To detect biofilm forming capacity of bacterial isolates obtained from the conjunctiva, contact lens and accessories of contact lens wearers using phenotypic and genotypic methods. Methods: Bacterial strains were collected from the conjunctiva, contact lens and lens storage cases of contact lens wearers. The phenotypic detection of biofilm production was done using the tube method and congo red agar method. The biofilm-forming related genes, icaA, of Coagulase negative Staphylococcus (CONS) and Staphylococcus aureus, and pslA, of P. aeruginosa, were detected using PCR. Results: A total of 265 bacterial isolates which included S. aureus, CONS, Pseudomonas, Nil-fermenter Gram-negative bacilli (NFGNB), Bacillus spp, Diphtheroids, Micrococci, Klebsiella pneumonia, Klebsiella oxytoca, E. coli, Proteus mirabilis, Proteus vulgaris, Citrobacter koseri, Citrobacter freundii, Enterobacter cloacae, Moraxella were obtained. Of the 265 isolates, 53.5% were moderately positive, 33.2% strongly positive and 13.2% negative for biofilm production by tube method and 36.6% were moderately positive, 40% strongly positive and 23.3% negative for biofilm production by congo red agar method. Of the four S. aureus isolates, two (50%) showed the presence of icaA gene. Of the 23 CONS isolates, three (13%) showed the presence of icaA gene. All the Pseudomonas isolates were negative for presence pslA (1119 bp) gene though most of them were phenotypically positive for biofilm formation. Conclusion: Most of the bacterial isolates obtained from contact lens wearers had the potential to produce biofilms. Tube method and Congo red agar method exhibited significant statistical correlation (P-value = 0.006) and picked up a good number of biofilm-forming isolates, hence may be used for detection of biofilm production. The absence of biofilm-forming gene did not rule out the possibility for phenotypic biofilm production by bacteria.

Frequency regulation in MG using conventional PID controllers becomes more challenging in the presence of stochastic load and uncertainty in system parameters caused by dynamic perturbation. So, there is a need for a robust controller with acceptable performance and stability for regulating the frequency in MG. The dynamic perturbations include changes in inertia constant and damping coefficient of the power system, which directly affect the frequency of the MG. In this paper, structured $\boldsymbol{H}_{\infty}$ synthesis has been done for robust frequency control in islanded MG. The sources used in MG for compensating the load demand are fuel cell, diesel engine generator and micro-turbine. The robustness and performance of $\boldsymbol{H}_{\infty}$ based controller is validated in the presence of parametric uncertainty and load disturbance caused by stochastic nature of load. The synthesized $\boldsymbol{H}_{\infty}$ based controller is tested for robust stability and performance against ± 50% perturbation of inertia constant and damping coefficient of power system. Simulation results of complete system is also validated with hardware using dSPACE 1104 and control desk.

Hospital-wide readmission rates recently became a recognized benchmarking quality metric. We sought to study the independent impact of major intraoperative adverse events (iAEs) on 30-day readmission in abdominal surgery.The 2007 to 2012 institutional American College of Surgeons National Surgical Quality Improvement Program and administrative databases for abdominal operations were matched then screened for iAEs using the International Classification of Diseases, 9th Revision, Clinical Modification-based Patient Safety Indicator "Accidental Puncture/Laceration". Flagged charts were reviewed to confirm the presence of iAEs. Major iAEs were defined as class 3 or above, as per our recently validated iAE Classification System. The inpatient database was queried for readmission within 30 days from discharge. Univariate and multivariable models were constructed to analyze the independent impact of major iAEs on readmission, controlling for demographics, comorbidities, American Society of Anesthesiology class, and procedure type/approach/complexity (using relative value units as proxy). Reasons for readmission were investigated using the Agency for Healthcare Research and Quality's International Classification of Diseases, 9th Revision, Clinical Modification-based Clinical Classification Software.Of 9,274 surgical procedures; 921 resulted in readmission (9.9%), 183 had confirmed iAEs, 73 of which were major iAEs. Procedures with major iAEs had a higher readmission rate compared with procedures with no iAEs [24.7% vs 9.8%, P.001]. In multivariable analyses, major iAEs were independently associated with a 2-fold increase in readmission rates [OR = 2.17 (95% CI = 1.22 to 3.86); P = .008]; 67% of readmissions after major iAEs were caused by "complications of surgical procedures or medical care" as defined by Agency for Healthcare Research and Quality.Major iAEs are independently associated with increased rates of 30-day readmission. Preventing iAEs or mitigating their effects can serve as a quality improvement target to decrease surgical readmissions.

Polycrystalline materials of Gd doped La1-xCaxMnO3 were prepared by Sol-Gel technique using citric acid as a chelating agent at 9000 C. The single phase formation of Gd doped LCMO were determined by Powder XRD, dielectric studies and impedance studies is investigated. The existence of dielectric relaxation and release of space charges were observed in the dielectric constant and real part of impedance plots respectively. The shift in the peaks for imaginary part of impedance revealed the existence of relaxation process due to oxygen vacancy. The existence of single semicircle in the cole-cole plot confirms the dielectric relaxation in the prepared sample.

The torque, power requirement and stir zone geometry during friction stir welding of AA2524 aluminum alloy were modeled by solving the equations of conservation of mass, momentum and energy. The model predictions agreed well with the corresponding measured values for a wide range of welding speeds and tool rotational speeds when the heat transfer coefficient and the friction coefficient values were adjusted.

Friction-stir welding is a refreshing approach to the joining of metals. Although originally intended for aluminium alloys, the reach of FSW has now extended to a variety of materials including steels and polymers. This review deals with the fundamental understanding of the process and its metallurgical consequences. The focus is on heat generation, heat transfer and plastic flow during welding, elements of tool design, understanding defect formation and the structure and properties of the welded materials.

Heat transfer and visco-plastic flow during friction stir welding of Ti-6Al-4V alloy have been modeled in three dimensions by numerically solving the equations of conservation of mass, momentum and energy using temperature dependent thermo-physical properties and temperature and strain-rate dependent viscosity values. The computed results showed that five important model parameters, i. e., the spatially variable friction coefficient, the spatially variable slip between the tool and the workpiece, the extent of viscous dissipation, the mechanical efficiency and the spatially variable heat transfer rate from the bottom surface of the workpiece significantly affected both the temperature fields and the computed torque on the tool. An important problem in the modeling of friction stir welding is that the values of these five parameters cannot be specified from fundamental principles and, and as a result, computed results are not always accurate. Here we show that by combining the heat transfer and plastic flow model with a genetic algorithm based optimization scheme, the values of the five uncertain parameters can be determined from a limited volume of experimental data so that the model predictions of peak temperatures and cooling rates match well with the experimental results. The computed results show that for the welding conditions reported in this paper, close to sticking condition prevailed at the tool – workpiece interface for all the experiments. The extent of viscous dissipation converted to heat was fairly low indicating lack of intimate atomic mixing in the stir zone. Computed three dimensional pressure distributions and streamlines were consistent with defect-free reliable welds for all conditions of welding studied.

Three-dimensional viscoplastic flow and heat transfer during friction stir welding of mild steel were investigated both experimentally and theoretically. The equations of conservation of mass, momentum and energy were solved in three dimensions using spatially variable thermo-physical properties and a methodology adapted from well-established previous work in fusion welding. Non-Newtonian viscosity for the metal flow was calculated considering temperature and strain rate dependent flow stress. The computed results showed significant viscoplastic flow near the tool surface, and convection was found to be the primary mechanism of heat transfer in this region. Also, the results demonstrated the strong three-dimensional nature of the transport of heat and mass, reaffirming the need for three-dimensional calculations. The streamlines of plastic flow indicated that material was transported mainly along the retreating side. The computed temperatures were in good agreement with the corresponding experimentally determined values.

Three-dimensional (3D) viscoplastic flow and temperature field during friction stir welding (FSW) of 304 austenitic stainless steel were mathematically modelled. The equations of conservation of mass, momentum and energy were solved in three dimensions using spatially variable thermophysical properties using a methodology adapted from well established previous work in fusion welding. Non-Newtonian viscosity for the metal flow was calculated considering strain rate and temperature dependent flow stress. The computed profiles of strain rate and viscosity were examined in light of the existing literature on thermomechanical processing of alloys. The computed results showed significant viscoplastic flow near the tool surface, and convective transport of heat was found to be an important mechanism of heat transfer. The computed temperature and velocity fields demonstrated strongly 3D nature of the transport of heat and mass indicating the need for 3D calculations. The computed temperature profiles agreed well with the corresponding experimentally measured values. The non-Newtonian viscosity for FSW of stainless steel was found to be of the same order of magnitude as that for the FSW of aluminium. Like FSW of aluminium, the viscosity was found to be a strong function of both strain rate and temperature, while strain rate was found to be the most dominant factor. A small region of recirculating plasticised material was found to be present near the tool pin. The size of this region was larger near the shoulder and smaller further away from it. Streamlines around the pin were influenced by the presence of the rotating shoulder, especially at higher elevations. Stream lines indicated that material was transported mainly around the pin in the retreating side.

Three-dimensional visco-plastic flow of metals and the temperature fields in friction stir welding have been modeled based on the previous work on thermomechanical processing of metals. The equations of conservation of mass, momentum, and energy were solved in three dimensions using spatially variable thermophysical properties and non-Newtonian viscosity. The framework for the numerical solution of fluid flow and heat transfer was adapted from decades of previous work in fusion welding. Non-Newtonian viscosity for the metal flow was calculated considering strain rate, temperature, and temperature-dependent material properties. The computed profiles of strain rate and viscosity were examined in light of the existing literature on thermomechanical processing. The heat and mass flow during welding was found to be strongly three-dimensional. Significant asymmetry of heat and mass flow, which increased with welding speed and rotational speed, was observed. Convective transport of heat was an important mechanism of heat transfer near the tool surface. The numerically simulated temperature fields, cooling rates, and the geometry of the thermomechanically affected zone agreed well with independently determined experimental values.

A genetic algorithms-based multioptimization study has been carried out for the hot rolling practice in an integrated steel plant. The aim is to identify the parameter settings and rolling schedules that would result in the optimum values of crown and flatness–-two major parameters related to the geometric tolerances in the rolled sheet. Two objective functions and some appropriate constraints have been formulated for this purpose, and two different evolutionary algorithms are tried out on them. The optimized results are presented in the forms of Pareto fronts and discussed in the context of the actual process.

A dimensionless correlation has been developed based on Buckingham's π-theorem to estimate the peak temperature during friction stir welding (FSW). A relationship is proposed between dimensionless peak temperature and dimensionless heat input. Apart from the estimation of peak temperature, it can also be used for the selection of welding conditions to prevent melting of the workpiece during FSW. The correlation includes thermal properties of the material and the tool, the area of the tool shoulder and the rotational and translation speeds of the tool. The peak temperatures reported in the literature during FSW of various materials and welding conditions were found to be in fair agreement with the proposed correlation.

To identify and compare the profile of retinopathy of prematurity (ROP) in premature babies in urban and semiurban neonatal intensive care units (NICUs).A prospective study of babies admitted to NICUs of two urban and seven semiurban centres. They were36 weeks of gestational age and were subjected to fundus photography with a RetCam shuttle camera. Photos and NICU details were uploaded on a secure website. Photographs were read by a single observer. Infants were followed till retinal vascularisation was complete, or 45 weeks post conceptional age. Babies developing severe ROP were lasered.500 babies were screened (243, urban group; 257, semiurban group). Incidence of ROP in the urban and semiurban groups was 16.5% (40) and 14.8% (38) respectively. Mean gestational age was 30.90 weeks and 31.53 weeks respectively. Mean birth weight was 1344 g and 1375 g respectively. 28 babies were lasered, 15 and 13 from each group respectively. There was no statistically significant difference between any of the parameters compared. Level of significance was fixed at 0.05.The magnitude of the burden of ROP is comparable between urban and semiurban NICUs stressing the need for effective screening strategies in semiurban and rural areas as well.

Acrolein and two sarcosines are combined to give the diazepanone substructure of the liposidomycin nucleoside antibiotics. Conformational analysis of the substituted diazepanone ring is presented.

Efficient chain extension of β-D-galactopyranosyl cyanide, cyclization to a bicyclic octose, and then attachment of cytosine affords the ezomycin octosyl nucleoside 17 in a form suitable for elaboration to the ezomycins (e.g., 1)

The structure of capuramycin (1) is confirmed by an efficient synthesis that features glycosylation with a D-manno-pyranuronate donor 16 at the hindered C-5' hydroxyl of L-talo-uridine 10

The liposidomycins comprise a family of complex nucleoside antibiotics that inhibit bacterial peptidoglycan synthesis. Their structures (1, 2) feature nucleoside, ribofuranoside, diazepanone, and lipid regions. Several stereogenic centers remain unassigned, including three within the diazepanone region: C-6‘, C-2‘ ‘‘, and C-3‘ ‘‘. An intramolecular reductive amination reaction has been used to prepare model diazepanones. Analysis of 40 and two of its diastereomers by NMR spectroscopy, X-ray crystallography, and molecular modeling indicates a close relative configurational and conformational match between 40 and the liposidomycin diazepanone degradation product 43 and allows the assignment of stereochemistry of the natural products as either [C-6‘(R), C-2‘ ‘‘(R), C-3‘ ‘‘(R)] or [C-6‘(S), C-2‘ ‘‘(S), C-3‘ ‘‘(S)].

Anastrozole tablets were subjected to different ICH prescribed stress conditions of thermal, hydrolysis, humidity, photolysis and oxidation stress. The drug was found to be stable for all the stressed conditions except for oxidation. Separation of anastrozole from its potential impurities, degradation products and five anastrozole related compounds as main impurities were achieved on Inertsil ODS-3V, 250 mm x 4.6 mm i.d, 5 microm analytical column using reversed phase high performance liquid chromatography (RP-HPLC). The elution of impurities employed time dependent gradient programmed mobile phase consisting of water as mobile phase-A and acetonitrile as mobile phase-B at column flow rates of 1 ml/min and at 215 nm UV detection. The same method was also extended to LC-MS/MS studies which were carried out to identify the degradation product. The method developed was established to have sufficient intermediate precision as similar separation was achieved on another instrument handled by a different operator. The LOQ for anastrozole related compound-A (RC-A), related compound-B (RC-B), related compound-C (RC-C), related compound-D (RC-D), related compound-E (RC-E) and anastrozole were 0.05, 0.03, 0.03, 0.06, 0.06 and 0.06 microg ml(-1) respectively. The linearity of the proposed method for all the above related compounds was investigated in the range of LOQ to 0.600 microg ml(-1) respectively. The specificity was established through peak purity testing using a photo-diode array detector. Method was validated according to ICH guidelines and statistical analysis of the data proved to be suitable for stability testing at quality control.

Efficient chain extension of β-D-galactopyranosyl cyanide, cyclization to a bicyclic octose, and then attachment of cytosine affords the ezomycin octosyl nucleoside 17 in a form suitable for elaboration to the ezomycins (e.g., 1)

The structure of capuramycin (1) is confirmed by an efficient synthesis that features glycosylation with a D-manno-pyranuronate donor 16 at the hindered C-5' hydroxyl of L-talo-uridine 10

The liposidomycins comprise a family of complex nucleoside antibiotics that inhibit bacterial peptidoglycan synthesis. Their structures (1, 2) feature nucleoside, ribofuranoside, diazepanone, and lipid regions. Several stereogenic centers remain unassigned, including three within the diazepanone region: C-6‘, C-2‘ ‘‘, and C-3‘ ‘‘. An intramolecular reductive amination reaction has been used to prepare model diazepanones. Analysis of 40 and two of its diastereomers by NMR spectroscopy, X-ray crystallography, and molecular modeling indicates a close relative configurational and conformational match between 40 and the liposidomycin diazepanone degradation product 43 and allows the assignment of stereochemistry of the natural products as either [C-6‘(R), C-2‘ ‘‘(R), C-3‘ ‘‘(R)] or [C-6‘(S), C-2‘ ‘‘(S), C-3‘ ‘‘(S)].

7617 Background: Personalized chemotherapy is an important advance for NSCLC pts. While genomic platforms have identified prognostic and predictive factors e.g., ERCC1 and RRM1/2, proteomic platfor...