Thio thiourea

PS—polystyrene UF—urea-formaldehyde resin glut—glutaraldehyde thio— thiourea BSA—bovine serum albumin PHEMA—poly(hydroxyethyl methacrylate) IDA—iminodiacetic acid LDH—lactate dehydrogenase OPS—o-phosphoserine 8HQ—8-hydroxyquinoUne Bpa— bis(2-pyridyl-methyl) amine. 

Mole Ratio = [reducing agent]/[dichromate] the ionic strength of control solutions was 0.349 THIO = thiourea BIS = bisulfite. 

Nitrogen nucleophiles used to diplace the 3 -acetoxy group include substituted pyridines, quinolines, pyrimidines, triazoles, pyrazoles, azide, and even aniline and methylaniline if the pH is controlled at 7.5. Sulfur nucleophiles include aLkylthiols, thiosulfate, thio and dithio acids, carbamates and carbonates, thioureas, thioamides, and most importandy, from a biological viewpoint, heterocycHc thiols. The yields of the displacement reactions vary widely. Two general approaches for improving 3 -acetoxy displacement have been reported. One approach involves initial, or in situ conversion of the acetoxy moiety to a more facile leaving group. The other approach utilizes Lewis or Brmnsted acid activation (87). 

Bases on the data of curve of the potentiometric titrations of [AuBr ] ions by thiourea (Thio), it consistently replaces bromide ions in [AuBr ] ion. They are formed mixed bromide-thiourea complexes of Au(III) AuBr Thio, AuBiyr/iio AuBrThio, AuBrThioJ. ... 

The only practical method for preparing alkylene thioureas is by the action of the diamines upon carbon disulfide in aqueous alcohol. The final heating is essential to convert the thio-carbamic acid into the cyclic compound, the addition of hydrochloric acid being beneficial. ... 

CARBAMIC ACID, ETHYL ESTER see URETHANE CARBAMIDE, THIO- see THIOUREA... 

The thio analogs are similarly prepared by using carbon disulfide instead of phosgene. These compounds react as cyclic ureas and thioureas. 

Disubstitution of 2,4-dichloropyrimidine with thiourea proceeds more readily than with hydrosulfide ion, principally because the former intermediate (229) contains the activating, cationic acylated thio group compared to the highly anionized mercapto group in the latter reaction. 

Faneti/ole (122) is a biological response modifier with significant immunosuppressant activity It can be synthesized by conversion of 2 phen> lethylamine (120) with ammonium thio cyanate to the corresponding thiourea analogue 121 The synthesis of faneli/ole (122) concludes by thiazole nng formation of 121 by reaction with phenacylbromide Thus its synthesis involves use of the classic Hantzsch procedure in which a bromoacetone analogue and an appropriate thio urea denvative are reacted 143]... 

When treated with alcoholic solution of ammonia, it yields thio-sinamine (allyl thiourea), of the formula C3H5. NH. CS. NHj. This body melts at 74°. The formation of this body forms the basis for a method of its determination, which, with other methods, will be found fully described under Oil of Mustard (Vol. I, p. 474). 

Thio-germaniumsaure, /. thiogermanic acid, -harnstoff, m. thiourea, -kohlensaure, /. thiocarbonic acid, specif, trithiocarbonic acid. H CSa. 

An acylated glycosyl halide, such as a 2,3,4,6-tetra-O-acetyl derivative, is treated with thiourea. The resulting pseudothiouronium salt is hydrolyzed with aqueous potassium carbonate to give the 2,3,4,6-tetra-0-acetyl-l-thio-(3-D-glucopyranose,48 which then is alkylated. 

Treatment of a chiral amine with phosgene is the cheapest way to prepare symmetrical ureas [29]. Nevertheless, due to the toxicity and reactivity of that reagent, it can advantageously be replaced by triphosgene [30] or l,l -carbonyldiimidazole [31-34] or other derivatives such as l,l -carbonyldi-2(lH)-pyridinone [35]. This procedure can be extended to thiophosgene (Scheme 1) and its thio-analogues, such as l,l -thiocarbonyldi-2(lH)-pyridinone to produce thioureas [36] chiral diamines can thus be transformed into the corresponding monoureas or monothioureas. 

Treatment of l- 6-[(/>-nitrophenyl)thio]-benzothiazol-2-yl thiourea 298 with bromine in chloroform yields 2-amino-7-[(/>-nitrophenyl)thio][l,2,4]thiadiazolo[3,2-/)]benzothiazolium bromide 299 (Equation 44) <2002MI15>. 

Wallis185 examined reactions of dimethyl 2-hexen-4-ynedioate with thioureas and thio-amides and observed addition at C-5 via the sulfur atom of these nucleophiles the adducts often cyclize spontaneously to iminothiazolidinones (equation 80). 

Propylthiouracil Propylthiouracil, 6-propyl-2-thio-2,4-(lH,3H)-pyrimidindione (25.2.2), is synthesized by condensating ethyl butyroacetate with thiourea in the presence of sodium ethoxide [13]. 

Curran[106] A/,A/ -diphenyl (thio)urea (10-100 mol%) first thiourea cat. Claisen rearrangements... 

Figure 6.3 Stereoselective, chiral thiourea derivatives of achiral benchmark thiourea organocatalyst N,N -bis [3,5-(trifluoromethyl)phenyl]thiourea 9 stereoselective hydrogen-bonding thiourea organocatalysts incorporating the privileged 3,5-bis(trifluoromethylphenyl)thiourea moiety. The (thio)urea catalyst structure is the leitmotif for the chapter organization.

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