Abstract: Too-Chien-Mu-Shi is the root of Aristolochia debilis Siebet Zuec.It has long been used as insecticide,antibacteria,haemostatic agengent and the treatment of round- worm and of brain hyperemia.Use as expectorant and stomachic had also been mentioned in the literature. 3 compounds (A,B,C) have been isolated by the author from the sample bought from the market of Shanghai."A," "C" were obtained from the upper and middle layers and B from the lower layer after the alcoholic extracts have been concentrated."A," "C" may be separated from each other by shaken with eher,to remove"A" (0.06% content) and then extracted with acetone,concentrated and stocked for a long time,some shining golden-yellowish flat form crystals separated out named "Too-Chien-Mu_Shi-C" (0.12% content) with the emperical formula C₃₃H₂₃NO₁₄,m.p.278-280°(D),a_D=±0. It is neither alkaloid nor glycoside. Under the examination of functional groups,it may exert NO₂,NO,CH₃ CO-C, (CH₃ CH(OH)),CO,C=λ_max 420 mμ,E_1cm.^1% 30,000(0.3g/C), Rf 0.79.Both physical and chemical properties of "C" are different to the alka- loids of Aristolochia spp.(Aristolochine,Aristinic acid,aristoliC acid,aristolochic acid,and isoaristolochic acid).While "A"(C₃₀ H₂₉ O₁₁ N,m.p.288-290°(D), a_D=±0),under the examination,is Probably an acidic compound,nitro- pseudo-acid,quinone,nitroso compound,alkyl-nitrate or alkyl nitrite.λ_{max 410mμ}^1%,1cm.= 7.68×10⁵ (0.14mg/c.c.),R_f 0.84. The lower layer of concentrated extract,having removed the "A" and "C", was concentrated to syrup and extracted with absolute alcohol.Concentrate the alcoholic extract.The colorless prism crystallic "Too-Chien-Mu-Shi-B" (0.22% content) C₄H₆N₄O₃,m.p.232-235,a_D=±0) is closely like to allantoin,and no depression of their mixed m.p.was observed. According to the chemical cnstitution of "Too-Chien-Mu-Shin",it is very closely related with the Chinese drug "Mufonchine" (A.Westlanch Hemst.Mu-ton A.Manchuriensis Komarov).