Isothiocyanates thioureas

If the acid hydrolysis of 1,3-oxazine derivatives is followed by acting with phenyl-isothiocyanate, thiourea derivatives can be formed. ... 

Epipolasin-B (61), mp 92 °C, was one of two isothiocyanates obtained from the sponge Epipolasis kushimotogensis. Neither the isonitrile nor formamido analog were found with the isothiocyanate. Instead, the thiourea adduct of /J-phenylethylamine was isolated along with another isothiocyanate-thiourea pair [51]. The absolute configuration of 61 was determined by appropriate... 

DeCaprio AP, Spink DC, Chen X, et al. 1992. Characterization of isothiocyanates, thioureas, and other lysine adduction products in carbon disulfide-treated peptides and protein. Chem Res Toxicol 5(4) 496-504. 

From 111 (cis or trans, R=H, Me), by reaction with phenyl isothiocyanate, thioureas 112 were prepared which, after a short refluxing in ethanolic hydrogen chloride, gave the cis- and trans-... 

Agents that are oxidatively activated and inactivate the enzyme by covalently binding to it include (a) diverse sulfur compounds (e.g., carbon disulfide , parathion -, diethyldithiocarbamate , isothiocyanates , thioureas , thiophenes , tie-nilic acid - - , and mercaptosteroids , (b) halo-genated structures such as chloramphenicoF- , A-monosubstituted dichloroacetamides , and N-(2-p-nitrophenethyl)dichloroacetamide , (c) alkyl and aryl olefins and acetylenes such as... 

Glycosyl-carbamates, -isothiocyanates, thioureas and Related Compounds... 

CH rCHCH NHCSNH. Colourless crystalline solid with a faint garlic-like odour m.p. 74 C. Manufactured by treating propenyl isothiocyanate with a solution of ammonia in alcohol. It has been given by injection in the treatment of conditions associated with the formation of excessive fibrous tissue. Toxic side reactions may occur. Propenyl thiourea is a chemical sensitizer for photographic silver halide emulsions. 

Aniinohexahydrobenzothiazole -when heated -with alkyl (299-301) or aryl (302) isothiocyanates yields the 1.3-substituted thioureas (138)... 

DiaminO 4,4-dimethyl-l,3,5-thiadiazine hydrobromide was isolated as by-product (418). Benzene sulfonates of cyanohydrin prepared from sodium cyanide and an halobenzoaldehyde, when treated with thiourea or its derivatives, afford 2,4-diamino-5-(p-halogenophenyl)-thiazole benzene sulfonates (447). Similarly, cyanoamido thiocarbamates obtained from cyanamide and isothiocyanates yield substituted 2,4-diaminothiazoles (598). 

Thioureas give thioxo analogues of a variety of the above syntheses (52JOC542), although these thioxo products are usually prepared from isothiocyanates (Section 2.15.5.2.1). Examples are known in the pyrido-[2,3-[Pg.225]

Several related derivatives have also been utilized in this type of synthesis. Imino-chloromethanesulfenyl chlorides (184), prepared by the controlled addition of chlorine to isothiocyanates, react with amidines (161) to give 1,2,4-thiadiazolines (185) (71T4117). Chlorocarbonylsulfenyl chloride (186), prepared by the hydrolysis of trichloromethanesulfenyl chloride with sulfuric acid, reacted with ureas, thioureas and guanidines to give 1,2,4-thiadiazolidine derivatives (187) <70AG(E)54, 73CB3391). 

This thiourea, prepared from an amino acid and phenyl isothiocyanate, is cleaved by anhydrous trifluoroacetic acid (an N-COCF3 group is stable), and by oxidation (/72-CIC6H4CO3H, 0°, 1.5 h, 73% yield H2O2/ACOH, 80°, 80 min, 44% yield). ... 

Chlorophenyl isothiocyanate has also been prepared by treating an alcoholic solution of sym-di-/)-chlorophenyl thiourea with iodine/ from ammonium -chloroplienyldithiocarbamate and lead nitrate/ (p. 72), and from the action of thiophosgene with /)-chloroaniline. ... 

Fluorophenyl isothiocyanate [1544-68-91 M 153.2, m 24-26 , 26-27 , b 66 /2mm, 215 /atm, 228 /760mm, n 1.6116. Likely impurity is the symmetrical thiourea. Dissolve the isothiocyanate in dry CHCI3, filter and distil the residue in a vacuum. It can also be steam distd, the oily layer separated, dried over CaCl2 and distilled in vacuo. Bis-(4-fluorophenyl)thiourea has m 145 (from aq EtOH). [Browne and Dyson J Chem Soc 3285 1931 Buu Hoi et al. J Chem Soc 1573 1955 Olander Org Synth Coll Vol I 448 1941 ]. 

Undoubtedly these reactions proceed via an intermediate ureido or thioureido derivative. These compounds have been obtained by Dornow and Hahmann by the action of potassium cyanate or ammonium isothiocyanate on 2-amino-4,6-dimethylnicotinic acid (11), but whereas the urea (12, X = 0) was converted into the pyrido[2,3-li]-pyrimidine-2,4(lI/,3/7)-dione (13, X = 0) by the action of heat, the thiourea (12, X = S) was unchanged after similar treatment. 

Altanserin (100) is a representative of the thiaquinazolinones. This serotonin antagonist is said to prevent gastric lesions. One method for preparation of this compound involves first preparation of isothiocyanate derivative 99, by reacting 4-fluorobenzoylpiperidine with 2-bromoethylamine and then converting the intermediate to the isothiocyanate with thionyl chloride and base. Condensation of 99 with methyl anthranilate (98) probably proceeds initially to a thiourea. Cyclization by ester-amide interchange leads to altanserin (100) [28]. 

Secondary butyl isothiocyanate, CH3. CH. CH(CH3). N C S, has been isolated from the oils of Cardamine amara and Cochlearia. It is a liquid with a powerful, irritating sulphur odour, having a specific gravity 0 9415 and boiling at 159° to 160°. Warmed with alcoholic solution of ammonia, it yields a thiourea, melting at 135° to 136°. 

The artificial cochlearia oil of commerce is not identical with secoudai-j-butyl isothiocyanate, but consists of isobutyl isothiocyanate. It is a liquid boiling at 162° and yields a thiourea, melting at 93-5°. 

Phenyl-ethyl isothiocyanate. CgHj,(C.2H4)N C S, has been found in the oils of reseda root, nasturtium, and some varieties of Brassica. It is an oil of powerful odour, yielding a thiourea, melting at 137°. The latter body, when treated with silver nitrate and baryta water, yields phenyl-ethyl-urea, melting at 111° to 112°. 

N,N Disubstituted thioureas from secondary amines and silicon tetra-isothiocyanate, 46, 69 N,N-Disubstituted ureas from secondary ammes and silicon tetraiso-cyanate, 46, 69... 

Condensation of 165 with ethoxymethylenemalononitrile gave 171, and with ethyl ethoxymethylenecyanoacetate or methyl bis(methylmercapto)-methylene cyanoacetate it yielded 172 (80AP108). The reaction of 172 with urea, thiourea, and benzyl nitrile afforded 173 (91PHA98). Treatment of hydrazino derivatives 165 with alkyl, aryl, or aralkyl isothiocyanates yielded (86JHC1731) 3-(/V-substituted-thiocarbamoyl)-hydrazino[l,2,4]triazino[5,6-b]indoles which have been evaluated for in vitro antimicrobial activity (Scheme 36). 

The reaction of 3-hydrazinophenanthro[9,10-e][l,2,4]triazine 742 with carbon disulfide, thiourea, phenyl isothiocyanate, urea, and phenyl isocyanate led [77ZN(B)569] to the formation of phenanthro[9,10-e][l,2,4]-triazolo[4,3-/j][l,2,4]triazines 743. Alkylation of 743 in aqueous alkaline... 

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