1,2-Aminothiols

Other Radioprotective Chemicals. The bis-methylthio- and methylthioamino-derivatives of 1-methylquinolinium iodide and l-methylpyridinium-2-dithioacetic acid provide reasonable protection to mice at much lower doses than the aminothiols, which suggests a different mechanism of action (139). One of these compounds, the 2-(methylthio)-2-piperidino derivative of the l-methyl-2-vinyl quinolinium iodide (VQ), interacts with supercoUed plasmic DNA primarily by intercalation. Minor substitutions on the aromatic quinolinium ring system markedly influence this interaction. Like WR-1065, VQ is positively charged at physiological pH, and the DNA-binding affinities of VQ and WR-1065 appear to be similar. 

Thiazolidines have been prepared from /3-aminothiols—for example, cysteine—to protect the —SH and — NH groups during syntheses of peptides, including glu-tathione. Thiazolidines are oxidized to symmetrical disulfides with iodine they do not react with thiocyanogen in a neutral solution. 

Because squaraines are sensitive toward nucleophilic attack resulting in decoloration and fluorescence quenching, they can be used as specific chemodosimeters for t/i/oZ-containing compounds. Squaraines 4 have been successfully applied as sensors for low-molecular-weight aminothiols like cysteine in a complex multicomponent mixture (e.g., human plasma) [91]. 

Sreejith S, Divya KP, Ajayaghosh A (2008) A near-infrared squaraine dye as a latent ratiometric fluorophore for the detection of aminothiol content in blood plasma. Angew Chem 120 8001-8005... 

In their efforts to construct a library of norephedrine aminothiol ligand analogues, Pericas and co-workers treated spiroaziridinium salts with sulfur nucleophiles to give /3-aminothioacetates (Equations 11 and 12) <2001SL1155>. The yield was not reported for thioacetate 38. The acetyl group was easily reduced with DIBAL-H resulting in the desired compounds. 

Several Pd11 complexes with thiolate or thioether derivative ligands have been studied to be applied in the hydroxycarbonylation reaction.394 Aminothiolate complexes of palladium with PPh3 catalyze the conversion of styrene to 2-phenylpropionic acid in high yield and excellent regioselectivity.644 Under mild conditions and in the presence of a catalytic amount of an S, TV-chelated palladium or//zo-amino-arenethiolate complex, styrene reacts with CO and oxalic acid or water to selectively give 2-phenylpropanic aid in high yield.645... 

The unexpected 1,5-benzothiazepine derivatives 135, with an exocyclic substituted double bond at the 4-position, were obtained in moderate yields (e.g. 135, R = 4-Me, 51%) on reaction of 134 with the aminothiol 136 in acetic acid. The structure of the products was confirmed by detailed ID and 2D NMR experiments <06H(68)1319>. 

This approach uses a kinetic sequential principle to carry out multicomponent CL-based determinations. In fact, when the half-lives of the CL reactions involved in the determination of the analytes in mixture are appreciably different, the CL intensity-versus-time curve exhibits two peaks that are separate in time (in the case of a binary mixture) this allows both analytes to be directly determined from their corresponding calibration plots. In general, commercially available chemiluminometers have been used in these determinations, so the CL reaction was initially started by addition of one or two reaction ingredients. Thus, in the analysis of binary mixtures of cysteine and gluthatione, appropriate time-resolved response curves were obtained provided that equal volumes of peroxidase and luminol were mixed and saturated with oxygen and that copper(H) and aminothiol solutions were simultaneously injected [62, 63],... 

Shestopalov, A. A. Clark, R. L. Toone, E. J. 2007. Inkless microcontact printing on self-assembled monolayers of Lmoc-protected aminothiols. /. Am. Chem. Soc. 129 13818-13819. 

Thiolation is restricted by more effective nitrogen donors or steric limitations. The bis(aminothiolate) complexes are obtained from bismuth nitrate or chloride and the hydrogen chloride adduct of the thiol and essentially independent of stoichiometry. The nitrogen-bismuth interactions in these complexes [e.g., Bi(SCH2CH2NH2)2(N03)(H20) 54,... 

The most effective synthetic control of the thiolation of bismuth has been achieved using reactions of bismuth chloride with aminothiolate salts (potassium) prepared in situ. Although the reactions are not quantitative, the molecular stoichiometry can be reliably selected and a systematic series of mono-, bis-, and tris-thiolates have been isolated and comprehensively characterized. (189). 

Seebach et al. (154) showed that a 0-isopropylidene-2,3-dihydroxy-l, 1,4,4-tetraphenyl-l,4-diol (TADDOL)-derived aminothiolate serves as a moderately effective ligand for the catalyzed conjugate addition of Grignard reagents to cyclic enones. The catalyst, synthesized from the lithiothiolate and CuCl, exhibits optimal selectivities under a slow addition protocol (2 h), Eq. 124. 

---