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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]

Abstract: Reaction of [(η5-C5Me5)MCl4], 1–2 (1: M=Mo and 2: W) with six fold excess of [LiBH4·thf] followed by thermolysis with excess chalcogen powders (S, Se and Te) yielded dichalcomolybda- and tungstaboranes, [(η5-C5Me5M)2B4H4E2], 5–8 (5: M=Mo, E=S; 6: M=Mo, E=Se; 7: M=Mo, E=Te; 8: M=W, E=Se) in modest yields. The geometry of 5–8 resembles a hexagonal bipyramid with a missing connectivity of two chalcogen vertices and a very short cross cage metal–metal bonding. All these new dichalcometallaboranes have been characterized by mass, 1H, 11B, 13C NMR spectroscopy, and the structural types were unequivocally established by crystallographic analysis of compound 6. [Copyright &y& Elsevier]

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 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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

The reaction of [Cp*TaCl4], 1 (Cp* = η5-C5Me5), with [LiBH4·THF] at -78 °C, followed by thermolysis in the presence of excess [BH3·THF], results in the formation of the oxatantalaborane cluster [(Cp*Ta)2B4H10O], 2 in moderate yield. Compound 2 is a notable example of an oxatantalaborane cluster where oxygen is contiguously bound to both the metal and boron. Upon availability of 2, a room temperature reaction was performed with [Fe2(CO)9], which led to the isolation of [(Cp*Ta)2B2H4O{H2Fe2(CO)6BH}], 3. Compound 3 is an unusual heterometallic boride cluster in which the [Ta2Fe2] atoms define a butterfly framework with one boron atom lying in a semi-interstitial position. Likewise, the diselenamolybdaborane, [(Cp*Mo)2B4H4Se2], 4 was treated with an excess of [Fe2(CO)9] to afford the heterometallic boride cluster [(Cp*MoSe)2Fe6(CO)13B2(BH)2], 5. The cluster core of 5 consists of a cubane [Mo2Se2Fe2B2] and a tricapped trigonal prism [Fe6B3] fused together with four atoms held in common between the two subclusters. In the tricapped trigonal prism subunit, one of the boron atoms is completely encapsulated and bonded to six iron and two boron atoms. Compounds 2, 3, and 5 have been characterized by mass spectrometry, IR, 1H, 11B, 13C NMR spectroscopy, and the geometric structures were unequivocally established by crystallographic analysis. The density functional theory calculations yielded geometries that are in close agreement with the observed structures. Furthermore, the calculated 11B NMR chemical shifts also support the structural characterization of the compounds. Natural bond order analysis and Wiberg bond indices are used to gain insight into the bonding patterns of the observed geometries of 2, 3, and 5. [ABSTRACT FROM AUTHOR]

The reinvestigation of an early synthesis of heterometallic cubane-type clusters has led to the isolation of a number of new clusters which have been characterized by spectroscopic and crystallographic techniques. The thermolysis of [(Cp*Mo)2B4H4E2] (1: E = S; 2: E = Se; Cp* = η5-C5Me5) in presence of [Fe2(CO)9] yielded cubane-type clusters [(Cp*Mo)2(μ3-E)2B2H(μ-H){Fe(CO)2}2Fe(CO)3], 4 and 5 (4: E = S; 5: E = Se) together with fused clusters [(Cp*Mo)2B4H4E2Fe(CO)2Fe(CO)3] (8: E = S; 9: E = Se). In a similar fashion, reaction of [(Cp*RuCO)2B2H6], 3, with [Fe2(CO)9] yielded [(Cp*Ru)2(μ3-CO)2B2H(μ-H){Fe(CO)2}2Fe(CO)3], 6, and an incomplete cubane cluster [(μ3-BH)3(Cp*Ru)2{Fe(CO)3}2], 7. Clusters 4-6 can be described as heterometallic cubane clusters containing a Fe(CO)3 moiety exo-bonded to the cubane, while 7 has an incomplete cubane [Ru2Fe2B3] core. The geometry of both compounds 8 and 9 consist of a bicapped octahedron [Mo2Fe2B3E] and a trigonal bipyramidal [Mo2B2E] core, fused through a common three vertex [Mo2B] triangular face. In addition, thermolysis of 3 with [Mn2(CO)10] permits the isolation of arachno-[(Cp*RuCO)2B3H7], 10. Cluster 10 constitutes a diruthenaborane analogue of 8-sep pentaborane(11) and has a structural isomeric relationship to 1,2-[{Cp*Ru}2(CO)2B3H7]. [ABSTRACT FROM AUTHOR]

Abstract In recent years, 1,4-triazole rings are being widely used for the synthesis of carbohydrate derived biomimetics, due to their easy synthesis and wide range of functional group compatibility. These triazole rings lead to synthetic molecules with improved enzymatic stability, bioavailability, and structural diversity. In this present work, a benzoyl group has been introduced at the C-5 position of the triazole ring present in the synthetic glycoconjugates providing further structural diversity to the molecule. 5-Benzoyl 1,4-triazole ring containing glycoconjugates were synthesized using Cu(I) catalyzed [3 + 2] cycloaddition reaction of per- O- acetylated glycopyranosyl azide and phenyl acetylene followed by in situ electrophilic addition of benzoyl group to the Cu(I) coordinated triazole intermediate. The X-ray crystal structure of one of the 5-benzoyl 1,4-triazole linked glycoconjugate derived from d -xylose {1- N -(2,3,4-tri- O -acetyl-β- d -xylopyranosyl)-4-phenyl-5-benzoyl-1,2,3-triazole} showed unique pattern of intermolecular C H...O interactions arranging the molecules in an anti-parallel orientation. The structure and morphology of the compounds were further explored using computational calculation and scanning electron microscopic (SEM) study which firmly established the uniqueness of 5-benzoyl 1,4-triazole linked glycoconjugates compared to that of 5-H 1,4-triazole linked derivative. Graphical abstract Image 1 Highlights • Single step synthesis of 5-benzoyl triazole linked glycoconjugates using [3 + 2] cycloaddition. • X-Ray crystal structure of one of the derivatives synthesized showed unique antiparallel arrangement of non-covalent interactions and DFT calculations showed good agreement with XRD data. • SEM study of the synthesized derivatives established the uniqueness of 5-benzoyl 1,4-triazole linked glycoconjugates compared to that of 5-H 1,4-triazole linked derivative. [ABSTRACT FROM AUTHOR]

Mahua oil cake (Bassia latifolia) is one of the non-conventional ingredients which are generally used as manure for horticultural crops. However, mahua oil cake can also be used as cheap source of nutrient for fish replacing conventional plant ingredient by solid state fermentation. Solid state fermentation of mahua oil cake was done by mixed strain of microbes (Sachharomyces cerevisiae and Bacillus subtilis) through a standard set of procedures which improved the quality of mahua oil cake by increase in crude protein, decrease in crude fibre and decrease in anti-nutritional factors like total tannin and saponin. To evaluate the fermented mahua oil cake in rohu, six iso‑nitrogenous feeds for rohu (Labeo rohita) were formulated and prepared incorporating fermented mahua oil cake at different levels i.e. 0, 10, 20, 30, 40 and 50% replacing soyabean meal and other feed ingredients and fed to rohu fingerlings in different treatment groups for 120 days period. Fish fed diets with 20% of mahua oil cake significantly improved (p < 0.05) growth performance, feed conversion ratio, digestibility of nutrients and immunological parameters like lysozyme, myeloperoxidase and haemagglutination compared to diets without fermented mahua oil cake. However, fish fed diets with 40% fermented mahua oil cake resulted non-significant difference (p > 0.05) in growth performance, nutrient digestibility and immunological parameters compared to diets without fermented mahua oil cake. The present study might suggest incorporation of solid state fermented mahua oil cake up to 40% level without interfering growth, digestibility and immunological parameters in L. rohita fingerlings. [ABSTRACT FROM AUTHOR]