Benzyl isothiocyanates, reaction with

A Wittig-type reaction of iminophosphorane 995 with benzoyl and ethoxycarbonyl isocyanates gave (91T6747) thiadiazolotriazines 996, whereas reaction of 995 with aromatic isocyanates afforded 997. On the other hand, iminophosphorane 995 reacted with methyl and benzyl isothiocyanates to give 998. Reaction of 995 with acid chlorides gave 999 (88H1935). All these compounds display mesoionic or zwitter ionic character (Scheme 184). 

Reaction of 255 first with 2% HC1 in MeOH and then with Et3N and benzyl isothiocyanate afforded 260 in 48% yield (Scheme 34).106,107 The reaction of 260 with 2-chloro-3-ethylbenzoxazolium tetrafluoroborate gave oxazoine 261(45%), hydrogenolysis of which gave oxazoline 262 in 45% yield. 

Toward a complete synthesis of trehazolin (2), 2,3,4,6-tetra-O-benzyl-1 -deoxy-z-D-glucopyranosyl isothiocyanate (7)52 was brought into reaction with the amines 5 and 374 in the presence of triethylamine to afford the x-D-glucopyranosyl thiourea derivatives 375 or 376, respectively (Scheme 46).38 Subsequent treatment with 2-chloro-3-ethylbenzoxazolium tetrafluoroborate and triethylamine afforded the corresponding amino oxazoline derivatives 377 and 378. Finally, hydrogenation over Pd(OH)2 on carbon afforded trehazolin (2). 

Dialkylaminothiocarbamoyl isothiocyanates react with carbodiimides to give [2+4] cycloadducts. [2 + 2 + 2] Cycloadducts 225 are obtained in the reaction of the shown carbodiimide 224 with methyl- or benzyl isothiocyanate. " The structure of the [2+ 2+2] cycloadducts were determined by X-ray crystallography. 

The aza-Wittig reaction is also used to form polymers with pendant carbodiimide groups. For example, reaction of the polymeric azide 31 with benzyl isothiocyanate and triphenylphosphine gives the corresponding carbodiimide 32, a precursor for oligomeric guanidines." ... 

Fig. 12. Toxication reactions catalyzed by GST. Examples of compounds that are not detoxified by conjugation with GSH include (a) ethylene dibromide, (b) trichloroethene, (c) hexachloro-1,3-butadiene, and (d) benzyl isothiocyanate.

The kinetics of the reaction of hydroxyl groups of monosaccharides and polyols with benzyl isothiocyanate has been checked by Augustin and Balaz using UV spectroscopy.289 However, because of the reversibility of the reaction, this procedure is not. of synthetic utility. O-Sugar thiocarbamates have been more conveniently prepared by aminolysis of thiocarbonate derivatives290,291 or by thiocarbamoylation of free hydroxy] groups with 1,1 -tbiocarbonyldiimidazoie.7 286 288... 

Subsequent reactions with n-octyl bromide, c-hexyl bromide, bromoacetaldehyde diethylacetal, benzyl chloride, oxirane, carbon dioxide, carbon disulfide (followed by reaction with methyl iodide), and methyl isothiocyanate. 

Organic isothiocyanates have been isolated from marine fauna and plants . Alkyl, allyl and benzyl isothiocyanates occur in nature as glucosinolates, in plants such as garden cress, horseradish and mustard. Their principal metabolite is a mercapturic acid (26) present in urine. It is analysed by decomposing at pH 5 according to reaction 41 the isothiocyanate is treated with -butylamine (reaction 39, X = S) and the resulting thiourea is extracted and analysed by HPLC. ... 

Scheme 40 Reaction of benzyl azide (200) with 2 equivalents of an aryl isothiocyanate 201 yields a thiadiazolidine 203 in the early stage of the reaction, and after Dimroth rearrangement of the latter, subsequently a more stable dithiazolidine 204 is formed [143]...

Zirconium. The long half life (78.4 h) of Zr, a positron emitter, is of particular interest to immuno-PET since it can enable the longer reaction times required for radioimmunodiagnostic applications and has been explored for its potential to act as a theranostic pair with and Lu. In 2005 van Dongen et al. chelated Zr to cetuximab via succinylated desferrioxamine B (A-sucDf) with p-benzyl isothiocyanate-l,4,7,10-tetra-azacyclododecane-l,4,7,10-tetraacetic acid (p-SCN-Bz-DOTA) and p-iso-thiocyanatobenzyl diethylenetriaminepentaacetic acid (p-SCN-Bz-DTPA) for comparisons with Lu and (was used in the place of Y). The data showed that the zirconium complexes could accurately predict the lutetium and yttrium biodistribution. Subsequently, van Dongen et al. 

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 l-benzyl-4-(acetylimido)-l/7-[l,2,4]triazolium inner salt 120 (an azomethine imine) with aromatic isothiocyanates yields among other products 5-acetyl-6-(arylimino)-l,5,6,7-anhydro[l,2,4]triazolo[3,4-A][l,3,4]thiadia-zoles 121 (Equation 34) <1984CCC1713>. 

The synthesis of the pyrimidine ring represents a well-studied group of heterocyclization reactions based on enamines. One of the important approaches involves the reaction of enamines with assorted isocyanates and isothiocyanates. Thus, a reaction of enaminonitriles with benzyl isocyanate or phenyl isocyanate gives C- and N-adducts (190a and 190b, respectively) or their mixtures, which are transformed in a single step into 4-pyrimidinone (191) and 2-pyrimidinone (192) derivatives (94JHC329). The... 

By contrast, the D-glucose isothiocyanate derivative 33 was synthesized from d-galactose pentaacetate 27 (Scheme 7) 51. Reaction of 27 with benzyl alcohol followed... 

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