Two novel alkaloids, goshuyuamide-I [4] and goshuyuamide-II [5] were isolated from the fruits of Evodia rutaecarpa, and their structures were determined on the basis of spectral data. The fruits of Euodia rutaecarpa Bentham (Rutaceae) have been used as a Chinese drug (Chinese name "Wu-Chu-Yu," Japanese name "Goshuyu") in the treatment of headache, abdominal pain, dysentery, postpartum hemorrhage, and amenorrhea (1). Phytochemical studies on the drug have shown the presence of numerous constituents including alkaloids such as evodiamine [1] (2), which was reported to increase arterial pressure (3). Our recent bioassay-directed research on the same drug led to the characterization of 1 as a powerful cardiotonic principle (4). During the fractionation, we also isolated N-(2-methylaminobenzoyl)tryptamine [2] and evodiamide [3], which are possibly key precursors of rarely occurring indolequinazoline alkaloids (5-10). Furthermore, our continuing in-depth study on the same material resulted in the isolation of two novel alkaloids, goshuyuamide-I [4] and goshuyuamide-II [5], whose structures are described in the present paper. The presence of an amide carbonyl and an indole chromophore in goshuyuamide-I [4], as observed in 1, was demonstrated by the IR and UV spectra (1620 cm⁻¹ and 225, 281.5, and 290 nm, respectively) (11). The molecular formula of C₁₉H₁₉N₃O for 4 was determined by HREIMS (m/z 305.1511 [M]⁺, Δ -1.7 mmu). The formula has two more hydrogen atoms than that of 1, suggesting that 4 might be a ring-opened structure of 1. The chemical shifts and multiplicities for 4 corresponded to those for 1 except those assignable to C-3. A doublet at δ 69.9 in 1 was replaced by a triplet at δ 44.8 in 4. In the ¹H-NMR spectrum, an aminomethyl appeared as a doublet (J=5.1 Hz) at δ 2.69, which was changed to a singlet by adding D₂O. These data could be readily interpreted in terms of only one possible structure, that is, goshuyuamide-I [4] was concluded to be 2-(2-methylaminobenzoyl)-1,2,3,4-tetrahydro-β-carboline. Goshuyuamide-II [5] analyzed for C₁₉H₁₇N₃O₂ by HREIMS (m/z 319.1310 [M]⁺, Δ -0.1 mmu). The functionality of the two oxygen atoms was established to be due to two amide carbonyls, because the IR spectrum showed a band at 1650 cm⁻¹ and the ¹³C-NMR spectrum revealed the absence of any C-O single bonds. In the ¹H-NMR spectrum there were three signals in the aliphatic regions. A three-proton singlet at δ 3.49 and two two-proton triplets (J=8.1 Hz each) at δ 3.46 and 4.65 were assigned to an aminomethyl and an ethylene adjacent to an indole nucleus, respectively. From the above observations 5 was deduced to be 3-[2-(3-indolyl)ethyl]-1-methyl-2,4-quinatolinedione. Compound 5 was previously prepared from 2 and methyl chloroformate by Bergman and Bergman (12). Our synthetic 5 was completely identical with the natural compound. The possibility that 5 was an artifact formed from 1 was ruled out, because no acidic conditions were used in any isolation processes of 5. As far as we know, 5 was obtained for the first time from natural sources. Further biogenetic and pharmacologic studies of 4 and 5 are in progress.