87122-95-0Relevant articles and documents
Regioselective Thermal [3+2]-Dipolar Cycloadditions of α-Diazoacetates with α-Sulfenyl/Sulfinyl/Sulfonyl-β-Chloroacrylamide Derivatives to Form Densely Functionalised Pyrazoles
Flynn, Aaran J.,Ford, Alan,Khandavilli, U. B. Rao,Lawrence, Simon E.,Maguire, Anita R.
supporting information, p. 5368 - 5384 (2019/06/24)
Highly regioselective synthetic methodology leading to densely functionalised C(3), C(4) and C(5) substituted pyrazoles 10a–q, 14a-i and 16a–g via thermal [3+2]-dipolar cycloaddition, of α-diazoacetates and α-thio-β-chloroacrylamides, at the sulfide, sulfoxide and sulfone levels of oxidation, is described. This method allows access to C(4)-sulfenyl or sulfonyl pyrazoles, through migration of the sulfur substituent at the sulfide and sulfone oxidation levels, while elimination of the sulfinyl group leading to 3,5-disubstituted pyrazoles, is observed. While the sulfide migration is readily rationalised, the carbon to carbon 1,2-sulfonyl migration is unprecedented and mechanistically intriguing. The synthetically versatile generation of densely functionalised pyrazoles containing substituents amenable to further modification offers advantages over alternative synthetic routes. Isolation of the N-alkylated pyrazoles 11a and 12a as by-products from the cycloaddition through further reaction of the pyrazoles 10 with excess α-diazoacetate, proved useful in rationalising the tautomeric behaviour evident in the NMR spectra of the pyrazoles, with the position of tautomeric equilibrium influenced by solvent and substituents.
2-(Arylthio)ethanamines and &α-(Arylthio)propionamides with Antidepressant Activity
Nair, M. D.,David, J.,Nagarajan, K.
, p. 940 - 947 (2007/10/02)
Reaction of aziridine with thiophenols affords 2-arylthioethanamines; with 2-methylaziridine, ring opening occurs regiospecifically to provide 1-arylthio-2-propanamines.The structure of one member of this group, 1-(4-chlorophenylthio)-2-propanamine (7), has been proved by other unambiguous syntheses. 7 and isomer 12 arise from the alkylation of 4-chlorothiophenol with 2-chloropropylamine as well as from the displacement of the tosyl group in 1-(4-chlorophenylthio)-2-tosyloxypropane (13).Alkylation of 4-chlorothiophenol with α-chloropropionamide affords 11 which leads to 12 on LAH reduction.Ethanamines and propanamines are converted into guanidines, amides, ureas and thioureas.Many arylthioethanamines, e.g. 7, 22, 28, 38 and 39 (as HCl salts) and α-arylthiopropionamides, e.g. 11, 86, 91, 93 and 96 exhibit good activity in the DOPA potentiation and reserpine antagonism tests.Among these, 7 HCl is the most potent and does not inhibit rat brain MAO activity.In clinical trials, C 2998-Go compares favourably with imipramine.
