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The present work describes the synthesis of a new class of glycolipids with systematic variations in the linkage region, as well as in the aglycon part using Cu(I) catalyzed click reaction. The linkage region between sugar and the aglycon part was diversified using amide, amido-triazole and 5-benzoyl triazole moieties. The structural diversity of glycolipids was further amplified by incorporating several polar peptide foldamer groups such as triazole, amide, peptide, or N-aryl peptoid in the aglycon part. The newly designed glycolipids were derived from the amalgamation of different peptide bond mimics. This work reports the first use of N-aryl peptoid in the synthesis of glycolipids. The newly synthesized glycolipids were characterized using different spectroscopic and spectrometric analyses. The impact of the amide bond as well as the triazole ring in the linkage region on the morphology of the glycolipids was analysed by comparing their self-assemblies using SEM analysis. The geometries of the glycolipids were also optimized using density functional theory and the optimized structures were found to be minima in the potential energy surfaces.

A series of novel 1,3-difunctionalized glycoconjugates were synthesized using a sequence of regioselective functionalization and stereoselective glycosidation of D-glucose and D-GlcNAc. Regioselective C-3 functionalization of sugar molecules was achieved by chemical functionalization of isopropylidene or oxazoline protected sugar derivatives. The structural diversity at the anomeric carbon was explored by stereoselective chemical glycosidation. The oxazoline protected D-GlcNAc derivative gave either pyranose or furanose derivatives on glycosidation depending on the amount of Lewis acid used. The diversely functionalized glycoconjugates with azide or alkyne groups are potentially useful for the synthesis of multifunctionalized complex glycoconjugates via click reactions.

Objectives: Peripherally inserted central catheter (PICC) lines are increasingly being used as a reliable central venous access in the management of patients on long-term intravenous medications. These are usually placed by different specialists; however, an intensivist-driven PICC line program with a dedicated clinic covering outpatient chemotherapy patients is an added avenue to our subspecialty. We share our experience of starting a PICC line clinic in our hospital and developing the team for insertion, maintenance, and troubleshooting of PICC lines, so to make this procedure smooth and complication free. Materials and Methods: We conducted a retrospective cross-sectional study of the first 100 consecutively placed PICC lines by intensivists at our hospital with our experience of starting a PICC line clinic. We analyze the success rates of PICC line placement under ultrasound guidance, also reporting complications encountered. Results: The initial 100 PICC lines placed in 92 patients during the 2-year study period having catheter days of 8674 days were analyzed. All the PICC lines were successfully placed (100%), the majority on chemotherapy patients (84%). A total of 39 complications were found in 16 patients, at a rate of 4.49/1000 catheter days; out of which only 2 (2%) cases had infection with septicemia. None of the 12 patients in the intensive care unit with catheter days of 164 days had any catheter-induced infection. Conclusions: Ultrasound-guided PICC line placement by an intensivist is a safe method in patients requiring prolonged intravenous medication. PICC line clinic increases awareness among such patients and makes the procedure with afterward care more standardized. [ABSTRACT FROM AUTHOR]

This research work is designed to overcome the problems associated with the poorly aqueous soluble drug. Fenofibrate (FENO) being a BCS Class II drug shows low solubility with high permeability. Compatibility of the drug and polymer studies was done by FTIR. Physical mixtures (PM) of the drug and polymer HPMCAS were prepared by the trituration method. Fenofibrate solid dispersions (SD) were prepared by a common solvent technique ascribed to feasibility on a laboratory scale. The physical state of formulations was characterized by powder XRD and TGA. Solubility of a pure drug (FENO), Physical mixture, and SD were found to be 0.3, 0.78±0.15 to 1.15±0.28, and 2.17±0.37 to 3.25±0.14 mg/ml respectively. Percentage yield and percentage drug content were determined and found within a satisfactory range. The maximum cumulative percentage of drug release from the pure drug (FENO), Physical mixture, and SD was found to be 34.5%, 72.1 and 97.2% respectively at 60 minutes. A microscopy (SEM) study found that the prepared solid dispersion has porous morphology. The present study establishes the increased bioavailability of the optimized batch when compared with the pure FENO. There was a significant (50%) increase in absorption of Fenofibrate observed from the in vitro everted gut sac model. SD of FENO was developed successfully. The solubility of FENO was ameliorated significantly while compared with API (pure FENO). This research work found the formulation of SD preferable technique to enhance solubility and enhance dissolution of lipophilic drugs. [ABSTRACT FROM AUTHOR]

This research work designed to overcome the problems associated with poorly aqueous soluble drug. Fenofibrate (FENO) being BCS Class II drug shows low solubility but permeability is high. Compatibility of the drug and polymer studies was done by FTIR. Physical mixtures (PM) of the drug and polymer HPMCAS were prepared by trituration method. Fenofibrate solid dispersions (SD) were prepared by common solvent technique ascribed feasibility in laboratory scale. Physical state of formulations was characterized by powder XRD, TGA. Solubility of pure drug (FENO), Physical mixture and SD found to be 0.3, 0.78±0.15 to 1.15±0.28 and 2.17±0.37 to 3.25±0.14 mg/ml respectively. Percentage yield and percentage drug content were determined and found within satisfactory range. The maximum cumulative percentage of drug release from pure drug (FENO), Physical mixture and SD found to be 34.5%, 72.1 and 97.2% respectively at 60 minutes. Microscopy (SEM) study was found that the prepared solid dispersion has porous morphology. The present study establishes the increased bioavailability of the optimized batch when compared with the pure FENO. There was significant (50%) increase in absorption of Fenofibrate observed from the in vitro everted gut sac model. SD of FENO was developed successfully. The solubility of FENO was ameliorated significantly while compared with API (pure FENO). This research work found formulation of SD preferable technique to enhance solubility and enhance dissolution of lipophilic drugs. [ABSTRACT FROM AUTHOR]

The reaction of the [(η5-C5Me5)MoCl4] complex with [LiBH4·THF] in toluene at -70 °C, followed by pyrolysis at 110 °C, afforded dark brown [(η5-C5Me5Mo)3MoB9H18], 2, in arallel with Ihe known [(η5-C5Me5Mo)2B5H9], 1. Compound 2 has been charactedzed in solution by ¹H, 11B, and 13C NMR spectroscopy and elemental analysis, and the structural types were unequivocally eslablished by crystallographic studies. The title compound represents a novel class of vertex-fused clusters in which a Mo atom has been fused in a perpendicular fashion between two molybdaborane clusters. Electronic structure calculations employing density functional theory yield geometdes in agreement with the structure determinations, and on grounds of density functional theory calculations, we have analyzed the bonding patterns in the structure. [ABSTRACT FROM AUTHOR]

Pyrolysis of (η5-C5Me5WH3)B4H8, 1, in the presence of excess BHCl2·SMe2 in toluene at 100 °C led to the isolation of (η5-C5Me5W)2B5H9, 2, and B−Cl inserted (η5-C5Me5W)2B5H8Cl, 3, and (η5-C5Me5W)2B5H7Cl2, 4−7 (four isomers). All the chlorinated tungstaboranes were isolated as red and air and moisture sensitive solids. These new compounds have been characterized in solution by 1H, 11B, 13C NMR, and the structural types were unequivocally established by crystallographic analysis of compounds 3, 4, and 7. Density functional theory (DFT) calculations were carried out on the model molecules of 3−7 to elucidate the actual electronic structures of these chlorinated species. On grounds of DFT calculations we demonstrated the role of transition metals, bridging hydrogens, and the effect of electrophilic substitution of hydrogens at B−H vertices of metallaborane structures. Reaction of (η5-C5Me5ReH2)2B4H4 with BHCl2·SMe2 led to the isolation of (η5-C5Me5ReH)2B5Cl5, while (η5-C5Me5WH3)B4H8 and an in situ generated intermediate, generated from (η5-C5Me5Mo)Cl4, and LiBH4, offer only partial chlorination at B−H vertices in (η5-C5Me5M)2B5H9 (M = W, Mo). DFT calculations were carried out on the model molecules of these chlorinated species; we demonstrated the role of transition metals, bridging hydrogens, and the effect of electrophilic substitution of hydrogens at B−H vertices of (η5-C5Me5M)2B5H9 (M = W, Mo). [ABSTRACT FROM AUTHOR]

Abstract: Reaction of (η5-C5Me5)MoCl4 with 6-fold excess of LiBH4·thf followed by pyrolysis with BHCl2·SMe2 in toluene at 90°C yielded known (η5-C5Me5Mo)2B5H9 (1) and B-Cl inserted (η5-C5Me5Mo)2B5H8Cl (2), (η5-C5Me5Mo)2B5H7Cl2 (3–5, three isomers) and (η5-C5Me5Mo)2B5H5Cl4 (6). In addition, reaction of (η5-C5Me5Mo)2B5H9 with 5-fold excess of n-BuLi followed by excess of MeI in THF yielded B-Me inserted metallaboranes (η5-C5Me5Mo)2B5H7(CH3)2 (7, 8 two isomers) and (η5-C5Me5Mo)2B5H6(CH3)3 (9, 10 two isomers). Isolated yields of 2–6 are poor but 7–10 are modest to good. Compounds 2–10 can be viewed as bicapped closo trigonal bipyramidal geometry. All the new compounds have been characterized in solution by IR, 1H, 11B, 13C NMR and mass spectroscopy as simple substitution derivatives of (η5-C5Me5Mo)2B5H9 and the structural types were unequivocally established by crystallographic analysis of compounds 2, 3, 5 and 6. [Copyright &y& Elsevier]

The reaction of [Cp*MoCl4] with an excess of LiBH4, followed by thermolysis with tellurium powder in toluene, afforded a tricapped cubane cluster, [(Cp*Mo)4B4H4(μ4-BH)3] (1), which represents an unprecedented metal-rich metallaborane cluster with a cubane core containing 58 cluster valence electrons (cve) and three metal-metal bonds. [ABSTRACT FROM AUTHOR]

The reaction of [Cp*MoCl(4)] with an excess of LiBH(4), followed by thermolysis with tellurium powder in toluene, afforded a tricapped cubane cluster, [(Cp*Mo)(4)B(4)H(4)(μ(4)-BH)(3)] (1), which represents an unprecedented metal-rich metallaborane cluster with a cubane core containing 58 cluster valence electrons (cve) and three metal-metal bonds.

Pyrolysis of (eta(5)-C(5)Me(5)WH(3))B(4)H(8), 1, in the presence of excess BHCl(2) x SMe(2) in toluene at 100 degrees C led to the isolation of (eta(5)-C(5)Me(5)W)(2)B(5)H(9), 2, and B-Cl inserted (eta(5)-C(5)Me(5)W)(2)B(5)H(8)Cl, 3, and (eta(5)-C(5)Me(5)W)(2)B(5)H(7)Cl(2), 4-7 (four isomers). All the chlorinated tungstaboranes were isolated as red and air and moisture sensitive solids. These new compounds have been characterized in solution by (1)H, (11)B, (13)C NMR, and the structural types were unequivocally established by crystallographic analysis of compounds 3, 4, and 7. Density functional theory (DFT) calculations were carried out on the model molecules of 3-7 to elucidate the actual electronic structures of these chlorinated species. On grounds of DFT calculations we demonstrated the role of transition metals, bridging hydrogens, and the effect of electrophilic substitution of hydrogens at B-H vertices of metallaborane structures.