Thiol ethers

Some proteins can be posttranslationally modified by the addition of prenyl groups. Prenyl groups are long-chain, unsaturated hydrocarbons that are intermediates in isoprenoid synthesis. The farnesyl group has 15 carbons, and the geranylgeranyl has 20 carbons. They are attached to a cysteine residue near the end of the protein as a thiol ether (Protein-S-R). Other proteins can have a long-chain fatty acid (C14=myristoyl, C16=palmitoyl) attached to the amino terminus as an amide. These fatty acid modifications can increase the association of proteins with the membrane. 

Sulfinpyrazone Sulfinpyrazone, l,2-diphenyl-4,2-(phenylsulfinil)ethyl-3,5-pyrazolidine-dione (3.2.8), is an analog of phenylbutazone that is synthesized in the analogous manner of condensing hydrazobenzol with 2-(2-phenyltioethyl)malonic ester into pyrazolidinedione (3.2.7), and the subsequent oxidation of thiol ether by hydrogen peroxide in acetic acid into the sulfoxide, sulfinpyrazone (3.2.8) [70,71]. 

A number of functional groups do not react with catecholborane These include organohalogen, alcohols and thiols, ethers, amides, nitro groups, and sulfones. Slowly reducing groups include acid chlorides, esters and nitriles. Aldehydes, ketones, imines, and sulfoxides are reduced. A hydroborating agent. 

Dithianes, thioacetals and -ketals, enol thiol ethers. This clay is a useful catalyst for reactions of ketones with thiols. The condensations are usually conducted in refluxing toluene with a Dean-Stark trap for water.1... 

SECTION 328 Alcohol, Thiol - Ether, Epoxide, Thloether... 

In nonbiological cell-free systems, acrolein has been shown to form thiol ethers within seconds when reacted with glutathione or cysteine (Esterbauer et al. 1975, 1976). In cell systems in vitro, such as... 

This is an example of several enzymes in which an essential co-factor is covalently bound to the protein. For example, lipoic acid and biotin are covalently linked to the c-amino group of a specific lysine residue in certain enzymes. In some cases, pyridoxal phosphate is bound to the protein through the formation of a Schiff base involving the carbonyl group of the co-factor and an c-amino group of a lysine residue. In cytochrome c, the heme is attached through two thiol ether linkages to cysteine residues of the protein. 

These lanthanide complexes produce spectral simplifications in the NMR spectrum of any compound with a relatively basic pair of electrons (an unshared pair) which can coordinate with Eu ". Typically, aldehydes, ketones, alcohols, thiols, ethers, and amines all interact ... 

N, v= valence of X). This class of Saturated Acyclic Monofunctional (SAM) derivatives includes amines, alcohols, thiols, ethers and thioethers. The emphasis was on keeping the program units as general as possible but tuning their heuristics to ensure drastic pruning, yet never allowing the correct structure to be absent from the final output of candidates. 

SECTION 328 ALCOHOL, THIOL - ETHER, EPOXIDE, THIOETHER... 

Adenosylmethionine + a thiol - S-adenosylhomocysteine + a thiole ether This enzyme catalyses this reaction with a variety of thiols and hydroxythiols. 

Alkyl Halides, Alcohols, Thiols, Ethers, Amines... 

A number of 2-heteroarylthiazoles were prepared including one with a thieno[2,3-l)]pyridine group on the thiazole (Scheme 51) (13SC59). A chloroacetamide-substituted thiazole reaas with 4,6-dimethyl-2-mercap-tonicotinonitrile to form the thiol ether, which cyclizes to form the thieno [2,3-b] pyridine. 

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