Thiourea compounds

Bis (meta or para haloacetyl) benzenes (C1CH2C0)2C6H4 condensed with thiourea yield the corresponding meta or para bis(4-thiazolyl-2-amino)phenylene (573, 574), analogous to 36 with R=NH2-By refluxing in alcohol solution m- or p-2-thiazolylphenacyl bromide (37) with thiourea, compound 111, in which R = H, Ph, P-CIC6H4, and p-OjNC H, was obtained (569). 

Scheme 36. The urea derivative gave similar results to the thiourea compound. Acyclic imines (mainly E isomers) and Z cyclic imines could also be used for this process (Scheme 40,91% ee) [148,152,154].

Thiourea and selenourea both form canal inclusion compounds. The selenourea compounds, reported only briefly 37), appear to be isostructural with the rhombo-hedral thiourea compounds, although with larger dimensions which are more susceptible to the sizes of guest molecules. For urea, thiourea and selenourea the crystal densities of the compounds are significantly less than those of the hosts values (g cm - 3) for the pairs host/complex are 1.30/1.20 1.40/1.10 2.08/1.60-1.65 for urea, thiourea, selenourea, respectively37). 

Thiourea compounds have been observed to inhibit human immunodeficiency virus (HIV) reverse transcriptase, a viral enzyme that is responsible for the reverse transcription of the retroviral RNA to proviral DNA. Phenethylthiazoylthiourea (PETT) compounds were discovered as potent inhibitors of HIV type 1 and display certain structure-activity relationships among various substituents in their structure.199 207 Furthermore, thiourea derivatives have been found to be potent and selective viral inhibitors, antifungal and antibacterial compounds.208 215... 

Rodenticides are clearly designed to kill animals and, thus, with the exception of thiourea compounds, are toxic to humans and should be avoided. Environmental concerns occur when other animals consume a poisoned rodent and are in turn poisoned. Eagles, wolves, and other animals high in the food chain are particularly vulnerable. 

The simply obtainable thiourea compounds 142-145 were the first organo-catalysts for the catalytic conjugate addition of indoles with nitroalkenes to yield optically active 2-indolyl-l-nitro derivative as 2.R-50 in fairly good yields and enantioselectivity. The simple thiourea-based organo catalyst 145 could be easily accessed in both enantiomeric forms from the commercially available materials. At the same time, the extremely simple methodology has proved the new approach useful for the synthesis of optically active target... 

Thiourea derivatives are known for their anti-thyroid effects due to inhibition of thyroid peroxidase [1], Two thiourea compounds especially, have found wide application in the treatment of patients with hyperthyroidism, i.e., PTU and 2-mer-capto-l-methylimidazole (methimazole). It was soon recognized, however, that while methimazole only blocks thyroid hormone synthesis PTU has an additional effect on thyroid hormone metabolism [13]. These clinical findings have been confirmed in vitro showing that PTU, but not methimazole, is a potent inhibitor of the type I deiodinase [5-8]. Structure-activity studies of thiourea analogues [44,45] have... 

Diafenthiuron is a thiourea compound. It is an insecticide and acaricide that kills the larval, nymphal, and adult stages of phytophagous mites and leaf-feeding insect pests by contact and stomach poison activity. Its oral LD50 in rats is 2068 mg/kg. 

A general method for the preparation of 9-substituted guanines has been recently developed by treatment of 1-alkylated AICA with benzoyl isothiocyanate, followed by hydrolysis and ring closure of the intermediate thiourea compound in the presence of a heavy metal ion (preferable Cu ) in aqueous sodium hydroxide. This procedure has been successfully used for the synthesis of guanosine (2). ... 

Lukovits, I., Palfi, K., Bako, I. and Kalman, E. (1997a). LKP Model of the Inhibition Mechanism of Thiourea Compounds. Corrosion, 53, 915-919. 

Zhang et al. investigated the asymmetric 1,3-dipolar cycloaddition of tert-butyl 2-(diphenylmethyleneamino)acetate and nitroalkenes promoted by bifunctional thiourea compounds derived from cinchona alkaloids, affording chiral pyrrolidine derivatives 13 with multisubstitutions. Catalyst lm delivered the best results in terms of catalytic activity, diastereoselectivity and enantioselectivity. Nevertheless, only moderate ee values could be obtained while the diastereoselectivities were generally good (Scheme 10.18) [22]. 

A study of the crystal field interaction in NdAlg by heat capacity, susceptibility, and resistivity measurements over the range 4—300K has been reported. Thermal transformations in thiourea compounds of neodymium, samarium, europium, and gadolinium have been shown to take place according to the scheme M(C3H302)3, CS(NH2)2,3H20 M(C3M,02) CSfNH ) NH CNS MO-... 

Comparison of the two mutant strains of B. megaterium, resistant to bacitracin and Su 2079, respectively, revealed that the 1735 cm" band was present in both cases, while the 1176 cm" band seen in the strain resistant to the thiourea compound was absent in the curve produced by the cells resistant to bacitracin. The strain resistant to the Su 2079 had a spectrum without a band at 835 cm". The 835 cm" band was distinct in the spectrum of the bacitracin-resistant cells. Thus, infrared spectroscopy differentiated between sensitive and resistant strains. 

In some cases, the polymerisation is performed in the presence of a thiourea compound as co-catalyst to extend the application of organo-catalysis towards less reactive monomers [63, 65, 69]. These compounds activate the carbonyl group via hydrogen bonding and thus render the carbonyl carbon more electrophilic as shown in Fig. 21.7. 

Scheme 4.8 Enantioselective Michael addition of malonates to nitroalkenes catalyzed by cinchona-thiourea compounds.

The 2-monosubstituted or disubstituted aminothiazoles obtained reaction between Halo carbonyl and N-substituted thiourea compounds [38]. 

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