Academic literature on the topic 'Powders (Pharmacy) ; Pharmaceutical chemistry'

2-amino-2-oxoacetic acid, carbamoyl formic acid, or oxamic acid is an active pharmaceutical ingredient (API) of great importance mainly because is an inhibitor of lactic dehydrogenase (LDH). It acts as an inhibitor to the metabolic pathways of the tumor cells and exhibited significant anticancer activity against nasopharyngeal carcinoma (NPC) cells in vitro and can be considered as a potential drug for the treatment of type 2 diabetes. Also, this compound could be used as a building block in the design of supramolecular architectures based on hydrogen bonds through the complimentary hydrogen-bond functionalities of the carbonyl and amide functional groups present. Single-crystal X-ray diffraction is the most powerful technique for crystal structure determination of small molecules. However, for several materials, including oxamic acid, it could be complicated to grow single crystals of suitable size and quality that make them appropriated to structure analysis. For this reason, the structural study was conducted with powder X-ray diffraction which is a process significantly more challenging than structure determination from single-crystal data. Oxamic acid has been characterized by FT-IR and NMR spectroscopic techniques, thermal TGA-DSC analysis, semi-empirical PM7 calculations, and X-ray powder diffraction. The title compound crystallizes in the monoclinic system with space group Cc, Z=4, and unit cell parameters a= 9.4994(4) Å, b= 5.4380(2) Å, c= 6.8636(3) Å, b= 107.149(2)°, V= 338.79(2) Å3. The molecule has a trans conformation. The molecular structure and crystal packing are stabilized mainly by intra- and intermolecular O--H···O and N--H···O hydrogen bonds. The structural characterization of this type of API compound is important to understand its mechanisms of action due to its considerable biological effects. In particular, for oxamic acid, this structural study would allow subsequent examination of its medicinal properties as an antitumor and antidiabetic agent.

The presence of chemical residues in aquatic environment can cause noticeable adverse physiological effects in humans and animals. In view of this, one needs methods to try to control its disposal, among these methods highlight the adsorption. The adsorption on solids is a phenomenon that focus on the surface of existing substances in liquids or gases. Due to the adsorption capacity of the derivatives of babassu (Orbignya phalerata, Mart.) and its abundance geographical took place this study was conducted with the purpose of transforming the coal into a potent babassu adsorbent useful for the treatment of industrial effluents, including pharmaceutical. The sieve analysis was performed and showed charcoal powder with a mean diameter of 500.475 mM, obtaining therefore a coarse powder. Potential adsorption system was elevated. According to the spectrophotometric reading, the initial concentration of methylene blue (3,85 mg/ml) was reduced to 0.106 g/ml in the system containing activated charcoal, thus resulting in a percentage adsorption equivalent to 97%. This study noted a keen perspective on the adsorption capacity of activated carbon from babassu front of the methodology employed. This material shows great potential for use in the manufacture of filters for the decontamination of industrial waste.

Thiohydantoins have been used in the manufacture of medicines and in industrial processes. Depending on the nature and type of substitution on the heterocyclic ring, these compounds may display pharmaceutical and biological activity with a variety of applications as antiepileptic, antitumoral, antiinflammatory, and principally for the treatment of prostate cancer. In this study, a new thiohydantoin was synthetized from the valine amino acid and structurally characterized. The title compound, C6H10N2O2S, with systematic name rac-5-isopropyl-2-tioxoimidazolidin-4-one, has been synthetized by a solvent-free synthesis. The heterocyclic compound was characterized by spectroscopic infrared (FTIR) and nuclear magnetic resonance (NMR) techniques, powder and single-crystal X-ray diffraction analysis (XRD). This material crystallizes in the monoclinic space group P21/c. In the supramolecular structure, the molecules are joined by N- --H···O and N---H···S hydrogen bonds, forming centrosymmetric R2 2(8) dimers and C2 2(9) chains that run along the [001] direction in an infinite one-dimensional network.

The aim of this study was to evaluate the influence of different methods of extraction solvents removal from liquid herbal drugs extracts on their pharmacological activity (immunomodulating, adaptogene, antioxidant and antibacterial). The authors used specific enzyme biotest systems in vitro based on key enzymes of antioxidant protection system - glutathione reductase and catalase, as well as on limiting enzyme of phagocytosis terminal phase – NADPH-oxidase, that allow the researchers to identify adaptogene, antioxidant, antibacterial and immunomodulating BAS activity and to estimate possible alterations in bioactivity of the studied objects. The obtained results showed that the drying temperature of liquid combined herbal drugs extracts does not influence significantly on its BAS complex bioactivity. Extract samples, dried at different temperatures, have immunomodulating and antibacterial activity. Best results were shown by the two samples: 1) dried at t=60 ± 1°С without vacuum application, and 2) preliminary adsorbed on the mix of powder like excipients isomalt GalenIQ® and Aeroperl® 300 Pharma, and then dried at room temperature. The materials of this article can be useful for specialists in pharmaceutical technology, biochemistry, and pharmacology. The obtained results contribute to the development of new advanced drug formulations based on BAS of herbal drugs extracts.

Despite Macfie's vivid assertion, studies of Victorian medicine and literature have not paid special attention to the pharmaceutical field, perhaps because of its messy associations with trade or inferiority to more respected healing practices. After all, it is Doctor Lydgate's refusal to prescribe the expected drugs inMiddlemarchthat proves his commitment to evidence-based Parisian medicine. As I aim to demonstrate, however, pharmacy and its products have a distinct and two-edged history in late-Victorian England. Medical writers increasingly assert the scientific authority and physiological promise of pharmacology. At the same time, they begin to show interest in the romance of drugs: their origins in alchemy and the occult, harvesting in the furthest outreaches of empire, and, at home, display in the magical space of the chemist's shop. This productive tension between medicinal drugs as stuff of ancient mystery and sign of medical progress informs their depiction in the transforming drug narratives of Robert Louis Stevenson'sStrange Case of Dr. Jekyll and Mr. Hyde(1886), Arthur Machen's “Novel of the White Powder” (1895), and Rudyard Kipling's “Wireless” (1902). Bringing romance and drugs together invites readers to think about their respective claims to invigorate, transport, even remake the self.

The literature contains conflicting reports on the effect of moisture on triboelectrification, indeed experiments have shown moisture to increase, decrease or have no effect at all on the charging of solids. The research programme investigated the role of moisture in the triboelectrification of a range of pharmaceutical excipients. Selection of excipients was made on the basis of a) moisture sorption capacity (the starch group) and b) potential use in dry powder inhaler formulations (the sugar and sorbitol group). The following excipients were selected for preliminary investigations:- a-lactose monohydrate, dextrose monohydrate, sorbitol spray dried (SSD), sorbitol powder, sucrose, maize and potato starch and Primojel™.

This thesis is 'concerned with aspects of dynamic compaction of pharmaceutical powders. The research is mainly aimed at the influence of compression rates on the residual resilience and strength of the tablet. A wide range of compression strain rates (103 - 10 per sec. ) is covered for di-pac-sugar, sodium chloride, potassium bromide, paracetamol, copper sulphate, avicel, lactose and calcium phosphate. The influence of compression rate on the form of the pressure-density relationship including the IHeckel and 1: awakita diagrams is investigated. Theoretical and experimental work are conducted on the relationship between radial and axial pressures during uniaxial straining. The general tendency for all the powders tested except for the paracetamol d. c., is to exhibit increased compaction pressure with strain rate up to 105 per sec. Due to morphological and compositional factors paracetamol d. c. softens with the rate of straining up to about 102 per sec. At higher rates it behaves like other powders. Generally, at high strain rates, the brittle behaviour dominates the process and tablet capping becomes more evident. The scope, origin and the main objectives of the present work are presented in Chapter 1. A brief historical account of the development of uniaxial compression techniques is given in'Chapter 2. Past work in the field of uniaxial compaction is reviewed and. classified. Various dynamic processes are classified according to the rates of compaction. Discussion of the various mechanisms responsible for, and governing, the way in which a powder consolidates when subjected to uniaxial compaction is presented together with a brief discussion of the capping phenomenon. Chapter 3 describes the construction and operation of a specially designed die incorporating a pressure pin for radial pressure measurement. The effect of compression rate on the form of the characteristic compaction curves, for all powders, is investigated using the above die on a servohydratlic variable speed machine (ICI simulator) at constant compression rate conditions (10-110 per sec). Investigations, using this apparatus indicate that all materials tested exhibit strain rate sensitivity to varying degrees (i. e. increased resistance to compaction as the speed is increased). In Chapter 4a brief review and discussion of viscoelastic aspects and theoretical modelling of the compaction process are presented. By plotting axial versus radial pressures during successive compression and decompression cycles at various speeds and by observing the decay of both pressures under constant volume conditions, it is possible toi draw certain conclusions about the relative elastic-plastic behaviour of each material. Investigations ' indicate that the use of linear viscoelastic theory could be useful in predicting the general trend of the process but insufficient to model the response of the various powders to the different loading conditions. Accurate modelling would require more experimental work and analysis of a high level. Also, the elastic recovery of all the compacts within the die is found to range from 8-120. Chapter 5 describes various aspects of forming and testing of tablets on an Instron machine at constant speed. Crack initiation, propagation and modes of failure during the Brazilian test are investigated by employing -high speed photography. An analysis of the effect of die and punch rigidity on the Kawakita relationship is attempted. An account of 'the variation of the. ejection pressure and the residual tensile strength with the maximum applied pressure is given. in this-chapter, the effect of ageing time and the effect of the ejection speed, for both straight and tapered dies, are also examined. Investigations indicate that, during the Brazilian test, in all compacts for all materials, the crack starts at the centre of the tablet and propogate up and down towards the plattens. Three main types (modes) of failure are observed: The 'traditional' mode of failure, in compacts of elastic-plastic deforming materials , (such like di-pac-sugar, paracetamol); The (random) mode of failure in plastically deforming compacts (such like sodium chloride potassium bromide), End capping which is observed in almost all materials compacted at high speeds. The values of the constant "b" (in the Kawakita Equation) is significantly influenced by the die and punch materials while the constant "a" remains unchanged. Also, the ejection pressure is increased with the increased axial maximum pressure and decreases with increasing speeds of compaction. All materials tested, show slight increase in the compact tensile strength as the. ageing time is increased - Also all compacts formed in the tapered die show higher tensile strength than those formed in the straight die over the range of ejection speed tested. Chapter 6 describes the construction and operation of an apparatus used for quasistatic"and medium rate (10 2_ 103 per sec) uniaxial compaction of powders. This apparatus allows the powder volume, 'axial and radial compaction pressures to be measured simultaneously. The investigations indicate that the properties of the resulting compacts are influenced by the compaction rate employed. Also, the compact tensile strength at this range is found to decrease together with the capping pressures. Chapter 7 describes the construction and operation of especially designed high pressure air projectile launcher compaction apparatus suitable for high rate uniaxial compaction of powders. Both, the axial pressure and powder volume can be measured on this apparatus. Problems of stress wave reflections in the system are overcome by using long load cells which enable accurate measurements to be obtained. Almost in all compacts, formed on this apparatus, ' end capping is observed. Chapter 8 gives a detailed description of the design, construction and operation of a high pressure triaxial cell working at pressures of up to 207 MPa, together with the associated equipment. Also, the sample preparation procedure is established. Preliminary, tests carried out on di-pac-sugar, lactose and paracetamol d. c. indicate that the powder characteristics can be designed by controlling the axial-and radial stresses. Chapter 9 describes the theory, equipment and the experimental results of a new technique based on the Split Hopkinson Bar principle to determine 'tension and compression Young's moduli of'a. tablet. The investigation indicates that the modulus in compression is higher than that in tension (in some cases by almost 20t). Finally, chapter 10 outlines general conclusions and suggestions for further work.

Parke-Davis was not the first drug company to put a statin on the market (Merck was), but it was the one to do it the best, with Lipitor (atorva statin). When Parke-Davis Pharmaceuticals in Ann Arbor, Michigan, began to look for its own statin in 1982, it was late in the game. Parke-Davis’s Lipitor was discovered in the mid- to late 1980s and brought to market in 1997. Already ahead of it were four statins: Merck’s Mevacor was released in September 1987 and Zocor in December 1991, Bristol-Myers Squibb’s Pravachol in October 1991, and Sandoz’s Lescol in March 1994. Despite the competition, by 2006 Lipitor had become the best-selling drug in history, with one-year sales totaling $12.9 billion, more than the net worth of the 10th biggest drug company in the world. Although the drug firm Parke-Davis had in recent times been relegated to history books, half a century ago, Parke, Davis and Company once enjoyed the status of the largest pharmaceutical manufacturer in the world. In 1866, 38-year-old Hervey C. Parke, a businessman, and Samuel P. Duffield, a chemist and physician, founded Duffield, Parke & Company— Manufacturing Chemists in Detroit, Michigan. Duffield originally studied under the father of organic chemistry, Justus von Liebig, at the University of Giessen in Germany. He continued to pursue his academic interests even after the founding of the company and published several articles in the American Journal of Pharmacy. In 1867, 22-year-old George S. Davis joined the company as the firm’s first salesman. Four years later, Parke and Davis bought out Duffield’s shares of the company. In November 1871, Parke, Davis & Company was born, with Parke as the president and Davis as the general manager. The company’s inventory was typical of the time: aconite, belladonna, ergot, spirit of ammonia, arsenic, and ether. Davis, a Napoleonic, small-statured man, was clearly responsible for building the company’s sales and its enterprise in many directions. He pioneered product promotion by publishing books and magazines, a practice later followed by many other companies. When vaccines were first invented in Europe, Parke-Davis was one of the first pharmaceutical companies to move into this new field.

Alcohols are usually protected as alkyl or silyl ethers. Michael P. Jennings of the University of Alabama found (Tetrahedron Lett. 2008, 49, 5175) that pyridinium tribromide can selectively remove the TBS (or TES) protection from the primary alcohol of a protected primary-secondary alcohol such as 1. Propargyl ethers are useful because they are stable, but can be selectively removed in the presence of other protecting groups. Shino Manabe and Yukishige Ito at RIKEN showed (Tetrahedron Lett. 2008, 49, 5159) that SmI2 could reductively remove a propargyl group in the presence of acetonides (illustrated, 3), MOM, benzyl and TBS ethers. Hisanaka Ito of the Tokyo University of Pharmacy and Life Sciences took advantage (Organic Lett. 2008, 10, 3873) of the reducing power of Cp2Zr to selectively remove the allyl ethers from 5, to give 6. These conditions might also remove propargyl ethers. Esters can also be useful protecting groups. Naoki Asao of Tohoku University developed (Tetrahedron Lett . 2008, 49, 7046) the o-alkynyl ester 7. Au catalyst in EtOH removed the ester, leaving benzoates, acetates, OTBS and OTHP intact. Alternatively, an o-iodobenzoate can be removed by Sonogashira coupling followed by the Au hydrolysis. N-Formylation is usually accomplished using mixed anhydrides. Weige Zhang and Maosheng Chang of Shenyang Pharmaceutical University put forward ( Chem. Commun. 2008 , 5429) an intriguing alternative, heating a secondary amine 9 with KCN in the presence of dimethyl malonate to give 10. Many of the current methods for amination that have been developed deliver the aryl amine. John F. Hartwig of the University of Illinois established (J. Am. Chem. Soc. 2008, 130, 12220) that exposure of the amine 11 to Boc2O followed by CAN led to the protected, dearylated amine 12. Adam McCluskey of The University of Newcastle observed (Tetrahedron Lett. 2008, 49, 6962) that microwave heating removed Boc protecting groups when there was a free carboxylic acid elsewhere in the molecule. Michael Lefenfeld of SiGNa Chemistry and James E. Jackson of Michigan State University used (Organic Lett. 2008, 10, 5441) easilyhandled Na/silica gel to remove primary and secondary sulfonamides (e.g. 15 → 16). Methanesulfonamides were also removed under these conditions.