So far more than 30 alkaloids have been isolated and identified from Papaver somniferum. Our company has been manufacturing morphine and the minor alkaloids by the Kabay-Bognár process from poppy straw (1). During the purification of narcotine, we detected a new substance. This paper describes the isolation and the structure elucidation of the new alkaloid. We could also detect this substance in opium from an Indian source. TLC studies (system A) demonstrated that the unknown substance was more polar than morphine or narcotoline. It gave a positive reaction with FeC13 referring to a phenolic hydroxy group. The new alkaloid yields natural narcotine after methylation with diazomethane in methanol. HPLC studies showed that the new substance and narcotoline had very similar behaviours, exhibiting the same retention time in most systems. We compared the IR spectrum of narcotine with that of the new substance. Both compounds showed a very intensive and characteristic lactone carbonyl stretching vibration (1758 cm⁻¹) also indicating the phthalideisoquinoline structure. The presence of a vOH band at 3400 cm⁻¹ confirms that the OH group is internally hydrogen bonded. El-MS studies revealed the molecular ion m/e 399 which was like the M of narcotoline. However, the base peak appeared at m/e 220, like in the case of narcotine. From the results we assumed that the new compound has the same substitution pattern as narcotine on the isoquinoline unit, but the former substance contains the free OH group on the phthalide skeleton. NMR data confirmed this assumption. We compared the ¹H-NMR spectra of narcotine, narcotoline, and O-demethylnarcotine. We changed the original assignments of the 8-OCH3 and 5'-OCH3 protons according to our detailed studies. The ¹H- and ¹³C-NMR spectra corroborated the structure of the new substance, which contains two methoxy groups and has the 5' -O-demethylnarcotine structure. Narcotine, narcotoline, and O-demethylnarcotine have the same coupling constants (³J₁,₉ = 4 Hz) for H-1 and H-9 protons, confirming the stereochemistry as well. Comparing the proton spectra of the compounds investigated, significant differences can be observed between the chemical shifts of the H-2' protons. These are due to the different substitution patterns of the phthalide skeleton. We carried out detailed assignments of the ¹³C-NMR spectra too. In the cases of narcotine and 5'-O-demethylnarcotine, we found significant differences in the chemical shifts of the phthalide moiety carbons. Comparing the ¹³C chemical shifts of narcotine and narcotoline, mostly carbons of the isoquinoline ring show differences (because of the 8-OCH3 → 8-OH change). Finally, we could achieve the chemical correlation as well. Surveying the literature, we realized that 5'-O-demethylnarcotine was prepared earlier by Schmidhammer and Klötzer (4). Repeating their experiments, the natural and semisynthetic 5' -O-demethylnarcotines proved to be identical (TLC, HPLC, NMR, IR). It is well established that scoulerine is the precursor of narcotine according to the studies of Battersby (5). It is conceivable that 5' -O-demethylnarcotine can fit to this biosynthetic pathway; The roots and rhizomes of Valeriana species and other genera belonging to the family Valerianaceae have been used in traditional medicine for centuries as a sedative. A large number of species in the genus Valeriana have been studied so far (1). We have been studying the constituents of the aerial parts of V. microphylla H. B. K. growing in Ecuador. Native Indian tribes use extracts of the plant as an antispasmolytical, stress-reducing, and sedative drug. To our knowledge V. microphylla has not been chemically investigated. In this report we describe the isolation and identification of 5 valepotriates (valtrate (1) (3), isovaltrate (2) (4), diavaltrate (3) (5), acevaltrat (4) (3), and didrovaltrate (5) (3)), of nardostachin (6) (6, 7), an iridoid which has not previously been recorded for the genus Valeriana, and of two lignans ((+)-1-hydroxypinoresinol (7) (8) and pinoresinol (8) (8)) (Fig. 1). This is the first time compounds belonging to the class of lignans have been reported for the Valeriana family. We have included the ¹³C-NMR data of 3 since these have not previously been reported. The valepotriates were isolated from the polar fractions of the petroleum ether extract by column chromatography. The raw ester fraction containing the valepotriates constituted 47% of the total petroleum ether extract. The compounds were purified by preparative TLC and HPLC, and the structures determined by spectroscopic techniques. The relative positions of the acyl groups were determined by ¹³C-NMR spectroscopy (9) and by identification of the decomposition products obtained by thermolysis, which gave information about the acyl group in the 11-position. The decomposition products, baldrinal and homobaldrinal (3), also appeared in the raw extract upon standing due to enzymatic hydrolysis. The valepotriates are considered as the major active component responsible for the sedative effect in drugs derived from the Valeriana species (10). Nardostachin was isolated in small amounts in the same fractions as the above-mentioned valepotriates and purified by HPLC. Nardostachin had been previously