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Dimethyl sulfoxide

Dimethyl sulfoxide is an organosulfur compound with the formula 2SO. This colorless liquid is an important polar aprotic solvent that dissolves both polar and nonpolar compounds and is miscible in a wide range of organic solvents as well as water, it has a high boiling point. DMSO has the unusual property that many individuals perceive a garlic-like taste in the mouth after contact with the skin. In terms of chemical structure, the molecule has idealized Cs symmetry, it has a trigonal pyramidal molecular geometry consistent with other three-coordinate S compounds, with a nonbonded electron pair on the tetrahedral sulfur atom. It was first synthesized in 1866 by the Russian scientist Alexander Zaytsev, who reported his findings in 1867. Dimethyl sulfoxide is produced industrially from dimethyl sulfide, a by-product of the Kraft process, by oxidation with oxygen or nitrogen dioxide; the sulfur center in DMSO is nucleophilic toward soft electrophiles and the oxygen is nucleophilic toward hard electrophiles.

With methyl iodide it forms trimethylsulfoxonium iodide, I: 2SO + CH3I → IThis salt can be deprotonated with sodium hydride to form the sulfur ylide: I + NaH → 2SO + NaI + H2 The methyl groups of DMSO are only weakly acidic, with a pKa = 35. For this reason, the basicities of many weakly basic organic compounds have been examined in this solvent. Deprotonation of DMSO requires strong bases like sodium hydride. Stabilization of the resultant carbanion is provided by the SR group; the sodium derivative of DMSO formed in this way is referred to as dimsyl sodium. It is a base, e.g. for the deprotonation of ketones to form sodium enolates, phosphonium salts to form Wittig reagents, formamidinium salts to form diaminocarbenes. It is a potent nucleophile. In organic synthesis, DMSO is used as a mild oxidant, as illustrated by the Pfitzner–Moffatt oxidation and the Swern oxidation. Related to its ability to dissolve many salts, DMSO is a common ligand in coordination chemistry. Illustrative is the complex dichlorotetrakisruthenium.

In this complex, three DMSO ligands are bonded to ruthenium through sulfur. The fourth DMSO is bonded through oxygen. In general, the oxygen-bonded mode is more common. DMSO is a polar aprotic solvent and is less toxic than other members of this class, such as dimethylformamide, dimethylacetamide, N-methyl-2-pyrrolidone, HMPA. DMSO is used as a solvent for chemical reactions involving salts, most notably Finkelstein reactions and other nucleophilic substitutions, it is extensively used as an extractant in biochemistry and cell biology. Because DMSO is only weakly acidic, it tolerates strong bases and as such has been extensively used in the study of carbanions. A set of non-aqueous pKa values for thousands of organic compounds have been determined in DMSO solution; because of its high boiling point, 189 °C, DMSO evaporates at normal atmospheric pressure. Samples dissolved in DMSO cannot be as recovered compared to other solvents, as it is difficult to remove all traces of DMSO by conventional rotary evaporation.

One technique to recover samples is removal of the organic solvent by evaporation followed by addition of water and cryodesiccation to remove both DMSO and water. Reactions conducted in DMSO are diluted with water to precipitate or phase-separate products; the high freezing point of DMSO, 18.5 °C, means that at, or just below, room temperature it is a solid, which can limit its utility in some chemical processes. In its deuterated form, it is a useful solvent for NMR spectroscopy, again due to its ability to dissolve a wide range of analytes, the simplicity of its own spectrum, its suitability for high-temperature NMR spectroscopic studies. Disadvantages to the use of DMSO-d6 are its high viscosity, which broadens signals, its hygroscopicity, which leads to an overwhelming H2O resonance in the 1H-NMR spectrum, it is mixed with CDCl3 or CD2Cl2 for lower viscosity and melting points. DMSO is finding increased use in manufacturing processes to produce microelectronic devices, it is used to strip photoresist in TFT-LCD'flat panel' displays and advanced packaging applications.

It used in biopreservation stem cell banking. DMSO is an effective paint stripper, being safer than many of the others such as nitromethane and dichloromethane; because of its ability to dissolve many kinds of compounds, DMSO plays a role in sample management and high-throughput screening operations in drug design. DMSO is used in polymerase chain reaction to inhibit secondary structures in the DNA template or the DNA primers, it is added to the PCR mix before reacting, where it interferes with the self-complementarity of the DNA, minimizing interfering reactions. DMSO in a PCR reaction is applicable for supercoiled plasmids or DNA templates with high GC-content. For example, 10% final concentration of DMSO in the PCR mixture with Phusion decreases primer annealing temperature by 5.5–6.0 °C. It is well known as a reversible cell cycle arrester at phase G1 of human lymphoid cells. DMSO may be used as a cryoprotectant, added to cell media to reduce ice formation and thereby prevent cell death during the freezing process.

10% may be used with a slow-freeze method, the cells may be frozen at −80 °C or stored in liquid nitrogen safely. DMSO has been used as a co-solvent to assist absorpt

Marquinhos Pedroso

Marcos "Marquinhos" Garbellotto Pedroso is a Brazilian professional footballer who plays as a left back. He made his professional debut for Figueirense FC at age 18. During his career in Figueirense, he was loaned out many times. In 2013 he was loaned to Guarani FC, in 2014 he was loaned to Gremio. In 2017, Marquinhos played while being loaned to Gaziantepspor; that year he was loaned to Ferencvárosi TC in Hungary. He was signed by FC Dallas on July 5, 2018, he was waived by FC Dallas on May 3rd, 2019. He played a total of 15 MLS games for Dallas. Marquinhos Pedroso joined D. C. United on May 3rd, 2019 after DC traded their 2020 MLS SuperDraft first round pick in exchange for $100,000 GAM from FC Dallas, he debuted against Sporting KC on May 12, 2019, where Marquinhos Pedroso and DC went on to win 1-0. DC United did not exercise his contract option after the 2019 season, he is a dual citizen of Italy. As of 2 June 2018. FigueirenseCampeonato Catarinense: 2014, 2015 Campeonato Catarinense Best Newcomer: 2014 Marquinhos Pedroso at Mackolik.com Marquinhos Pedroso at Soccerway

Saltire

A saltire called Saint Andrew's Cross or the crux decussata, is a heraldic symbol in the form of a diagonal cross, like the shape of the letter X in Roman type. The word comes from Middle Latin saltatoria. From its use as field sign, the saltire came to be used in a number of flags, in the 16th century for Scotland and Burgundy, in the 18th century as the ensign of the Russian Navy, for Ireland. Notable 19th-century usage includes some of the flags of the Confederate States of America, it is used on seals, as a heraldic charge in coats of arms. The term saltirewise or in saltire refers to heraldic charges arranged as a diagonal cross; the shield may be divided per saltire, i.e. diagonally. A warning sign in the shape of a saltire is used to indicate the point at which a railway line intersects a road at a level crossing. In Unicode, a decussate cross is encoded at U+2613 ☓ SALTIRE. See X mark for similar symbols; the saltire is one of geometric charges that span throughout the shield. As suggested by the name saltire, the ordinary in its early use was not intended as representing a Christian cross symbol.

The association with Saint Andrew is a development of the 15th to 16th centuries. The Cross of Burgundy emblem originates in the 15th century, as a field sign, as the Saint Andrew's Cross of Scotland was used in flags or banners from the 16th century, used as naval ensign during the Age of Sail; when two or more saltires appear, they are blazoned as couped. For example, contrast the single saltire in the arms granted to G. M. W. Anderson—with the three saltires couped in the coat of Kemble Greenwood. Diminutive forms include the fillet saltire considered half or less the width of the saltire, the saltorel, a narrow or couped saltire. A field per saltire is divided into four areas by a saltire-shaped "cut". If two tinctures are specified, the first refers to the areas above and below the crossing, the second refers to the ones on either side. Otherwise, each of the four divisions may be blazoned separately; the phrase in saltire or saltirewise is used in two ways: Two long narrow charges "in saltire" are placed to cross each other diagonally.

Common forms include the crossed keys found in the arms of many entities associated with Saint Peter and paired arrows. When five or more compact charges are "in saltire", they are arranged with one in the center and the others along the arms of an invisible saltire. Division of the field per saltire was notably used by the Aragonese kings of Sicily beginning in the 14th century, showing the pales of Aragon and the "Hohenstaufen" eagle; the Flag of Scotland, called The Saltire or Saint Andrew's Cross, is a blue field with a white saltire. According to tradition, it represents Saint Andrew, supposed to have been crucified on a cross of that form at Patras, Greece; the Saint Andrew's Cross was worn as a badge on hats in Scotland, on the day of the feast of Saint Andrew. In the politics of Scotland, both the Scottish National Party and Scottish Conservative Party use stylised saltires as their party logos, deriving from the flag of Scotland. Prior to the Union the Royal Scots Navy used a red ensign incorporating the St Andrew's Cross.

With its colours exchanged, the same design forms part of the arms and flag of Nova Scotia. The Cross of Burgundy, a form of the Saint Andrew's Cross, is used in numerous flags across Europe and the Americas, it was first used in the 15th century as an emblem by the Valois Dukes of Burgundy. The Duchy of Burgundy, forming a large part of eastern France and the Low Countries, was inherited by the House of Habsburg on the extinction of the Valois ducal line; the emblem was therefore assumed by the monarchs of Spain as a consequence of the Habsburgs bringing together, in the early 16th century, their Burgundian inheritance with the other extensive possessions they inherited throughout Europe and the Americas, including the crowns of Castile and Aragon. As a result, the Cross of Burgundy has appeared in a wide variety of flags connected with territories part of the Burgundian or Habsburg inheritance. Examples of such diversity include the Spanish naval ensign, the flag of Carlism, the flag of the Dutch capital of Amsterdam and municipality of Eijsden, the flag of Chuquisaca in Bolivia and the flag of the US state of Alabama.

The naval ensign of the Imperial Russian and Russian navies is a blue saltire on a white field. The international maritime signal flag for M is a white saltire on a blue background, indicates a stopped vessel. A red saltire on a white background denotes the letter V and the message "I require assistance"; the Brazilian cities of Rio de Janeiro and Fortaleza use a blue saltire on a white field, with their coats-of-arms at the hub. The flags of the Spanish island of Tenerife and the remote Colombian islands of San Andrés and Providencia use a white saltire on a blue field. Saltires are seen in several other flags, including the flags of Grenada, Alabama, Jersey, Logroño, Amsterdam, Katwijk and Valdivia, as well as the former Indian princely states of Khairpur and Jaora; the design is part of the Confederate Battle Flag and Naval Jack used during the American Civil War (see Flags