99841-06-2

Upstream product

• 110-85-0 piperazine 
• 118-55-8 phenyl Salicylate 
• 69-72-7 salicylic acid 
• 61141-14-8 anionic phenyl salicylate 

Downstream Products

• 151824-81-6 5-(4-Salicyloylpiperazin-1-yl)-2-nitroaniline 
• 151824-78-1 5-(4-Salicyloylpiperazin-1-yl)-1,2-phenylenediamine 

Relevant academic research and scientific papers

Effects of mixed H2O-CH3CN solvents on the Bronsted coefficient for the intramolecular general base-catalyzed cleavage of ionized phenyl salicylate in the presence of primary and secondary amines

Nucleophilic second-order rate constants, knms, for the reactions of several primary and secondary amines with ionized phenyl salicylate (PS-) show a nonlinear decrease with the increase in the content of CH3CN from 2 to ≤50% v/v in mixed aqueous solvent. The values of knms remain almost unchanged with the change in the content of CH3CN at >50% v/v. The nucleophilic reactivity of primary and secondary amines toward PS- reveal Bronsted plots of different Bronsted coefficients, βnuc, at a constant content of CH3CN in mixed aqueous solvents. The values of βnuc decrease from 0.4 to nearly 0 for primary amines and from 0.22 to 0.12 for secondary amines with the increase in CH3CN content from 2 to 70% v/v. The values of knms/kMeOHms (where kMeOHms represents the nucleophilic second-order rate constant for the reaction of MeOH with PS- in H2O-CH3CN solvents), obtained within 2-50% v/v CH3CN, fit to an empirical equation: log (knms/kMeOHms) = θ+λX where X is the % v/v content of CH3CN, and θ and λ are empirical constants. It has been shown empirically that both θ and λ are the function of Bronsted coefficient βlg. The values of λ are used to calculate βlg and these βlg values for all amines except Tris lie within -0.32 to -0.46. The effects of mixed water-acetonitrile solvents on pKa of leaving the group, phenol, and conjugate acid of amine nucleophile have been concluded to be the major source for the observed solvent effects on knms. The βlg for Tris is unusually very close to zero.

Solvent effect on intramolecular general base-catalysed aminolysis of ionized phenyl salicylate

The nucleophilic second-order rate constants (k1) for the reactions of ionized phenyl salicylate (PS-) with primary and secondary amines in 70percent (v/v) ethanol-water reveal Bronsted plots of slopes βnuc1 = 0.32 +/- 0.10 and βnuc2 = 0.22 +/- 0.02, respectively.Different Bronsted slopes obtained for the reactions of PS- with primary and secondary amines suggest the occurrence of different locations of the transition state in the critical rate-determining step.The change in water content from 99.2 to 70percent (v/v) in EtOH-H2O causes reduction in k1 by ca. 3-fold for all the amines studied.Ionization constants of all the protonated amines turn out to be larger in 70percent (v/v) EtOH-H2O than in pure water.

Synthesis and potential anthelmintic activity of methyl-5-(4-salicyloyl-piperazin-1-yl)-benzimidazole-2-carbamates

A series of methyl-5-(4-salicyloyl-piperazin-1-yl)-benzimidazole-2-carbamates (IX) has been prepared. 5-(4-salicyloyl-piperazin-1-yl)-2-nitro anilines (VII) have been synthesized starting from 5-piperazino-2-nitro anilines and salicyloyl chlorides. Catalytic reduction of VII with Pd/C, followed by treatment with 1,3-dicarbomethoxy-S-methyl isothiourea, yielded the corresponding carbamates (IX), the anthelmintic activity of which was studied. Compound IX(a) significantly reduced the numbers of preadults, adults and encysted T. spiralis larvae in experimental mice.