Aminoiminomethanesulfonic acid

Preparative Methods by the oxidation of thiourea or amino-iminomethanesulfinic acid (formamidinesulfinic acid) with peracetic acid. Many substituted aminoiminomethanesulfonic acids can be prepared in the same way. 2 Others have utilized hydrogen peroxide with sodium molybdate as a catalyst to oxidize the corresponding thioureas to a variety of monosubsUtuted aminoiminomethanesulfonic acids the substituents include phenyl, 2-methylphenyl, 4-fluorophenyl, / -propyl, cyclohexylmethyl, S-a-methylbenzyl, cyclooctyl, and benzhydiyl.  

Purification recrystaUize from glacial acetic acid. 

Handling, Storage, and Precautions stable for at least a few weeks at room temperature. After drying, it remains stable for 

A list of General Abbreviations appears on the front Endpapers 

Reaction of aminoiminomethanesulfonic acid with a vari ety of amino acids gives 3delds of guanldlno acids rang Ing from 5-80%. Reactions of some amino acids do not lead to an isolable product. Similar results are obtained with (phenylamlno) Imlnomethanesulfonic acid and (phenylamlno)-(phenyllmlno) methanesulfonic acid.  

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Shown below are some other electrophiles that have been used to form guanidines from amines. The pyrazole derivatives 820 have been used extensively in peptide syntheses.21 The aminoiminomethanesulfonic acid derivative 922 might be the intermediate formed when thioureas are oxidized and then reacted with amines to form guanidines certainly 9 is a useful... 

Kim, K. Lin, Y.-T. Mosher, H. S. Monosubstituted Guanidines from Primary Amines and Aminoiminomethanesulfonic Acid, Tetrahedron Lett. 1988,29, 3183-3186. 

The syntheses of substituted 5-aminotetrazoles 228, using azide ions for assembling the tetrazole scaffold, can be divided into two different approaches. The first approach is the addition of sodium azide to car-bodiimides 222 [156,157] or cyanamides 223 [158-161]. The second approach is the nucleophilic substitution of a chlorine in a-chloroformamidines 224 [162], the nucleophilic substitution of benzotriazole in (benzotria-zolyl)carboximidamides 225 [163], the nucleophilic substitution of the sxflfite anion in aminoiminomethanesulfonic acids 226 [164] and the nucleophilic substitution of sulfur from thioureas 227 in the presence of mercury [165] or lead [ 166-169] salts in the presence of an azide ion (Scheme 43). In this chapter, the main focus is on the addition of azides to carbodiimides 222 to form substituted 5-aminotetrazoles 228. 

Other Nucleophilic Substitution Reactions. Nucleophilic substitution of a variety of substituted aminoiminomethanesulfonic acids with cyanide leads to the corresponding aminoimi-noethanenltrlles in 30-87% yield. A number of substituted aminoiminomethanesulfonic acids react with sodium azide in acetic acid to give the corresponding 5-aminotetrazole. This reaction Is subject to pronounced steric hindrance. Hydroxyl-amine and cyanamlde also give nucleophilic substitution of the sulfonic acid group. ... 

Scheme 12 Completion of the synthesis of zanamivir and 2,3-unsaturated sialic acid (Neu5Ac2en) analogues. Reagents and conditions a) Me3SiN3 (1.5 equiv), t-BuOH, 90 °C, 13 h 96% b) i) ln(0) (2 equiv), NH4CI, EtOH, 80 °C, 12 h ii) LiOH, THE, rt, 2 h 90% for the 2 steps c) aminoiminomethanesulfonic acid, K2CO3, water, 77% d) LiOH (2 equiv), THE, rt, 2 h 90%.

Aminoiminomethanesulfonic acid N-tert-Butyl, in A-60210 Methionine sulfoximine, M-70043... 

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