2273-39-4

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The present invention discloses an N-alkyl-N-cyanoalkylbenzamide compound of General Formula I, an intermediate of General Formula II used to prepare the compound, wherein R1 is selected from halo or C1-C3 alkyl; R2

The present invention discloses a pyrazolamide compound of General Formula I having an insecticidal activity and an intermediate of General Formula II used to preparing the compound of General Formula I, wherein R1 is selected from chloro or CN

The molecular structure of 1,5,5-trimethyl-3-acetyltetramic acid (I) and its Schiff-bases with ethylendiamin (II) and 1,3-diaminopropan-2-ol (III) is described by an equilibrium of four tautomers.The solvent dependence of the equilibrium is attributed to the strength of the intramolecular hydrogen bond.The higher proton affinity of the Schiff-bases (II and III) in comparison with the ketone (I) should be responsible for the faster equilibration of II and III.

The Bucherer-Bergs reaction provides an important tool for the synthesis of α-aminoacids and is the basis of an industrial process for producing methionine.The key compound is the α-aminonitrile 1 which leads to partial decomposition in carbonate buffer as well as in weakly basic aqueous media and to the equilibrated formation of the basic intermediate α-carboxy-aminonitrile 2a.The parameters which control the stability of 2a are summarised.These equlibria are established through an initial fast step which is then followed by the formation of the hydantoin 5a.At a constant pH this formation is first order in α-carboxyaminonitrile 2a via a 5-imino-2-oxazolidinone 3a and an α-isocyanatamide 4a.A comparison of the reactivity of 1 with that of the N-alkylated compouds 7 shows that the rate determining step of the hydantoin formation is the cyclisation of 2a at pH9.But at higher pH, the reaction is controlled by the fast partitioning of the cyclic intermediate 3a between the α-carboxyaminonitrile 2a and the isocyanatamide 4a.This study permits the direct comparison between two mechanism for the synthesis of the racemic α-aminoacids: the Bucherer-Bergs way and the catalytic hydratation of α-aminonitriles.It is clear that carbonic anhydre can be considered as a special carbonyl compound with respect to its reactivity towards α-aminonitriles.

Dans le cadre de l'etude de la reaction de Bucherer-Bergs (transformation, en solution aqueuse, d'un compose carbonyle en acide α-amine correspondant via l'α-aminonitrile puis l'imidazolidinedione-2,4) le comportement d'α-alcoylaminonitriles en presence de CS2 est examine et elargi au systeme α-alcoylaminonitriles/CO2 en solution aqueuse.En presence de CS2, l'α-aminonitrile conduit a la formation equilibree d'imino-5 thiazolidine thione-2.Son evolution ulterieure vers l'imidazolidine dithione-2,4 alcoyle-1 est bloquee par la substitution sur l'azote 3.Par contre, nous avons mis en evidence la formation inattendue de l'imidazolidine dithione-2,4 non substituee.En solution aqueuse et en presence de CO2, l'imino-5 oxazolidinone-2 que nous n'avons pas decelee doit etre en equilibre tres defavorise avec l'α-carboxyaminonitrile.Les seules reactions observees sont l'hydratation autocatalitique de l'α-aminonitrile et sa decomposition en hydroxy-2 propionitrile et en α-aminodinitrile.

Compounds of the general formula I: EQU1 in which R1 - R4 which may be the same or different represent hydrogen atoms, or C1-6 straight or branched chain alkyl, alkenyl or alkynyl group or an alkyl group substituted by a cycloalkyl group, or represents a cycloalkyl, alkoxycarbonyl, aryl, arakyl, acyl (which includes anylsulphonyl) groups in which the alkyl group or the alkyl portion of the aralkyl group may be substituted with one or more hydroxy or esterified hydroxy groups and in which the aryl groups or the aryl portion of the acyl or aralkyl group may be substituted by one or more halogen atoms, alkyl groups, hydroxy groups, alkoxy groups, trifluoromethyl, nitro, amino or dialkylamino groups, and in which R5 - R8 which may be the same or different represent hydrogen atoms or alkyl groups except that not all groups may be hydrogen, or R5 and R6 or R7 and R8 together represent a carbonyl (=O) oxygen and in any of the pairs of groups R1 /R2, R3 /R4, R5 /R6 and R7 /R8 may represent a carbocyclic or heterocyclic ring system optionally substituted by lower alkyl or aryl groups, said ring being saturated or unsaturated. These compounds have utility as oral analgesics.

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