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Pyrrole is an extremely weak base for an amine, with a conjugate acid pK a of −3.8. The most thermodynamically stable pyrrolium cation (C 4 H 6 N +) is formed by protonation at the 2 position. Substitution of pyrrole with alkyl substituents provides a more basic molecule—for example, tetramethylpyrrole has a conjugate acid pK a of +3.7.
Pyrrolidine, also known as tetrahydropyrrole, is an organic compound with the molecular formula (CH 2) 4 NH. It is a cyclic secondary amine , also classified as a saturated heterocycle . It is a colourless liquid that is miscible with water and most organic solvents.
Intravenous sugar solution, also known as dextrose solution, is a mixture of dextrose (glucose) and water. [1] It is used to treat low blood sugar or water loss without electrolyte loss. [ 2 ] Water loss without electrolyte loss may occur in fever , hyperthyroidism , high blood calcium , or diabetes insipidus . [ 2 ]
Synthesis of nucleosides involves the coupling of a nucleophilic, heterocyclic base with an electrophilic sugar. The silyl-Hilbert-Johnson (or Vorbrüggen) reaction, which employs silylated heterocyclic bases and electrophilic sugar derivatives in the presence of a Lewis acid, is the most common method for forming nucleosides in this manner.
Inverted sugar syrup [1] – Pursuant to Code of Federal Regulation 21CFR184.1859, invert sugar is an "aqueous solution of inverted or partly inverted, refined or partly refined sucrose, the solids of which contain not more than 0.3 percent by weight of ash. The solution is colorless, odorless, and flavorless, except for sweetness.
At the sides of nucleic acid structure, phosphate molecules successively connect the two sugar-rings of two adjacent nucleotide monomers, thereby creating a long chain biomolecule. These chain-joins of phosphates with sugars ( ribose or deoxyribose ) create the "backbone" strands for a single- or double helix biomolecule.
Derivatives of tetrahydropyran are, however, more common. 2-Tetrahydropyranyl (THP-) ethers derived from the reaction of alcohols and 3,4-dihydropyran are commonly used as protecting groups in organic synthesis. [2] Furthermore, a tetrahydropyran ring system, i.e., five carbon atoms and an oxygen, is the core of pyranose sugars, such as glucose.
However, the linear, free-aldehyde structures that Fischer proposed represent a very minor percentage of the forms that hexose sugars adopt in solution. It was Edmund Hirst and Clifford Purves, in the research group of Walter Haworth , who conclusively determined that the hexose sugars preferentially form a pyranose, or six-membered, ring.