Guanidine hydrochloride, reaction with

According to the new model the structural element(s) of apoCopC is changed by the binding of Cu(II), from one-kind structural element(s) changing to two-kind structural elements, which one is more stable than another. Naturally the equilibrium-imfolding reaction of the protein displays three-state behavior. The data ( ) measured guanidine hydrochloride experiment with Cu -CopC are fitted well in eq (19). 

Rolgamidine (14) is a dihydropyrrole derivative which has antidiarrheal activity It can be synthesized by alkylation of trans 2,5-dimethyl-3 pyrroline (12) with methyl bromoacefate to give 13 An amide-ester exchange reaction with guanidine hydrochloride completes the synthesis of rolgamidine (14) [3]... 

Step C Preparation ofthebase-A 300 ml one-necked, round-bottomed flask, equipped with a water-cooled condenser, calcium chloride tube and magnetic stirrer is charged with anhydrous methanol (150 ml) and sodium metal (5.75 g,0.25 g atom). When the reaction is complete, the solution is treated with dry guanidine hydrochloride (26.3 g, 0.275 mol) and stirred for 10 minutes. The sodium chloride that forms is removed by filtration. The solution is concentrated in vacuo to a volume of 30 ml and the residue treated with the product of Step B, heated one minute on a steam bath and kept at 25°C for 1 hour. The product is filtered, washed well with water, dissolved In dilute hydrochloric acid and the free base precipitated by addition of sodium hydroxide to give the amllorlde product base, a solid which melts at 240.5°-241.5°C. 

It is also possible to quantitatively convert all water oxygen directly to CO2 by reaction with guanidine hydrochloride (Dugan et al. 1985) which has the advantage that it is not necessary to assume a value for the H2O - CO2 isotope fractionation in order to obtain the ratio. On-line pyrolysis using TC-EA systems repre-... 

Reaction of 3,5-bisarylmethylene-l-ethyl-4-piperidone with thiourea or guanidine hydrochloride in alcoholic KOH afforded the pyrido[4,3-, pyrimidine derivatives 605 and 606, respectively <2001IJB213>. 

Guanidine Resin (23). A suspension of Merrifield resin (5 g, 1.7 mmol Cl/g resin) in DMF (100 ml) was treated with guanidine hydrochloride (5 g) and a solution (1 M) of potassium tert-butoxide in THF (50 ml). The resulting reaction mixture was heated at 90° for 24 h. Upon cooling, the resulting resin was filtered and washed with DMF/DBU (7 3), DMF, di-oxane, water, THF, and ethyl ether. The resin thus produced was dried under vacuum at RT overnight. 

The 111.6 kg resultant precipitates of N"-[4-(chloromethyl)-4,5-dihydro-4-hydroxy-2-thiazolyl]-guanidine hydrochloride are collected, and washed with 50 L of acetone. In 500 ml of water are dissolved 111.6 kg of N"-[4-(chloromethyl)-4,5-dihydro-4-hydroxy-2-thiazolyl]-guanidine hydrochloride and 32.9 kg of thiourea. The solution is stirred for one hour at 50°C. N -[4-[[(Aminoiminomethyl)thio]methyl]-2-thiazolyl]-guanidine dihydrochloride is formed in the reaction mixture, and this reaction mixture containing this compound is directly used for the next process without isolation of the formed compound. 

The reaction of the tetrafluoroethylene trimer with guanidine hydrochloride in dry ether forms light-sensitive 2-amino-4,5,6-tris(trifhioromethyl)pyrimi-dine 100 in a high yield (98JFC(88)169). 

It was established (01IZV457) that the products of the reaction of per-fluoro-2-methylpent-2-ene and perfluoro-5-azanon-4-ene with guanidine hydrochloride in the presence of triethylamine are 4-fluoro-6-pentafluoro-ethyl-5-trifhioromethyl-pyrimidin-2-ylamine 101, whose structure was confirmed by X-ray analysis (Fig. 4) and compound 102, respectively. 

Note that in the case of the reaction of guanidine hydrochloride with perfluoro-5-azanon-4-ene one obtains a mixture of products 102 and 103. Compound 103 is the product of further reaction of perfluoro-5-azanon-4-ene with 102. It may be assumed that 103 is formed according to the following scheme ... 

The Step 1 product (4.97 mmol) dissolved in 15 ml methyl alcohol was treated with a mixture of sodium ethoxide (4.97 mmol) and guanidine hydrochloride (5.22 mmol) and the reaction was then monitored by TLC using 15% EtOAc/toluene. The mixture was then concentrated and the residue dissolved in EtOAc. The residue was purified by chromatography using 15% EtOAc/toluene and the product isolated in 95% yield. 

The thiols in native lipoamide dehydrogenase are remarkably unreac-tive with other reagents only one thiol is at all reactive with DTNB or iodoacetate (61). Formation of the TNB-enzyme mixed disulfide is greatly increased by low concentrations (0.7 M) of guanidine hydrochloride (166). Its modification is associated with the destabilization of the enzyme in 1 Af guanidine hydrochloride which results in the slow reaction of 6 additional thiols. If the denaturant and excess DTNB are removed when the single thiol has reacted, the spectrum of enzyme-bound FAD is unmodified and the enzyme retains almost full activity. It is concluded that the thiol and the FAD are remote from one another in the protein (166). 

Another variation of the Biginelh condensation involved the reaction of aldehyde 42, guanidine hydrochloride with various pyrazolones 41 to provide pyrazo-lopyrimidines 43 (Scheme 10) [30]. All the products obtained were tested against the M. tuberculosis H37 Rv strain and found to be active. In particular, compounds 44-46 had comparable activity (MIC =1.2 pg/mL) to first-Une drugs such as rifampicin (RIP) (MIC = 1 pg/mL). 

Reaction of 13 [R2 = C(4-CH,OC6H4)(C6H5)2] with guanidine hydrochloride in the presence of sodium hydride in dry dimethylformamide at 20 CC gives l-[2,3-dideoxy-2,3-(2-iminoimidazo-lidino)-5-0-[(4-methoxyphenyl)diphenyImethyl]-/ -D-ribofuranosyl]uracil 18 in 54% yield, while 13 (R2 = H) under similar conditions gives the dimeric iV1,W3-a-fused-(2-iminoimidazo-lidine)uridine 19 in 35% yield106. 

To the partially reduced GDNF was added 100 il of 0.2 M NEM followed by 100, 1 of 6 M guanidine hydrochloride in 0.25 M Tris containing 1 mM EDTA at pH 8.5. The reaction was allowed to occur at room temperature for 30 min in the dark before it was quenched by adjusting the pH to 2.0 with 25% TFA. The modified protein was pvnified by reverse phase chromatography as described in the previous section. 

A suitable protein derivative is dissolved in 5.0 M guanidine hydrochloride at pH 8.0, and solid succinic anhydride (50 moles/mole of amino group) is added in small portions to a rapidly stirred solution at room temperature. The pH is maintained (by means of a pH-stat) by the addition of M NaOH. When the addition of succinic anhydride is complete, solid hydroxylamine hydrochloride is added to the reaction mixture to a concentration of 1 M, the pH is adjusted to 10 with NaOH and the mixture allowed to stand at room temperature for... 

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