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Lycopodium alkaloids 1 such as serratinine (4) and lycodoline (5), possessing a common formula of C 16 N, and lucidines A and B, with that of C 30 N 3 , are a class of natural products with unique ring systems, which have attracted great interest from biogenetic, 1,2 synthetic, 1,3 and biological 4 points of view. These unique skeletons have prompted us extensive phytochemical work. In our search for biogenetic intermediates of Lycopodium alkaloids, three new alkaloids, serratezomines A (1), B (2), and C (3), with a seco-serratinine-type, a serratinine-type, and a lycodoline-type skeletons, respectively, were isolated from the club moss Lycopodium serratum var. serratum. In this paper, we describe the isolation and structure elucidation of 1-3.The club moss L. serratum var. serratum 5 collected in Sapporo were extracted with MeOH, and the MeOH extract was partitioned between EtOAc and 3% tartaric acid. Water-soluble materials, which were adjusted at pH 10 with saturated Na 2 CO 3 , were partitioned with CHCl 3 . CHCl 3 -soluble materials were subjected to a C 18 column (CH 3 CN/0.1% CF 3 CO 2 H, 1:4 f 4:1), in which a fraction eluted with CH 3 CN/0.1% CF 3 CO 2 H (1:4) was purified by an amino silica gel column (CHCl 3 /MeOH, 1:0 f 1:1) followed by C 18 HPLC (CH 3 CN/0.1% CF 3 CO 2 H, 13:87) to afford serratezomines A (1, 0.0002% yield), B (2, 0.002%), and C (3: 0.0002%) as colorless solids together with known related alkaloids, serratinine (4, 0.02%), 6 lycodoline (5, 0.004%), 7 and L20 (6, 0.004%). 8 The molecular formula, C 16 H 25 NO 3 , of serratezomine A (1) was established by HRFABMS [m/z 280.1926, (M + H) + , ∆ +1.3 mmu]. IR absorptions implied the presence of hydroxyl (3400 cm -1 ) and ester carbonyl (1730 cm -1 ) functionalities. 1 H and 13 C NMR data (Table 1) disclosed the existence of one ester carbonyl, one sp 3 quaternary carbon, five sp 3 methines, eight sp 3 methylenes, and one secondary methyl. Among them, two methines (δ c 76.24; δ H 3.77 and δ c 83.57; δ H 4.32) were ascribed to those bearing an oxygen, while one methine (δ c 66.80; δ H 3.81) and two methylenes (δ C 56.04; δ H 3.35 and 3.54 and δ C 48.76; δ H 2.98 and 3.26) were ascribed to those attached to a nitrogen. Since one out of five unsaturations were accounted for, 1 was inferred to possess 4 rings. St. Laurent, D. R.; Friedrich, D.; Pinard, E.; Roden, B. A.; Paquette, L. A. references cited therein. (4) The club moss L. serratum has been used as Chinese traditional medicine, in which the constituent alkaloids, hupderzines A and B, show pronounced anticholinesterase activity and are under clinical investigation in China for the treatment of myasthenia gravis and senile memory loss now recognized as symptoms of Alzheimer's dementia (AD): Liu, J. S.; Zhu, Y. L. Yu, C. M.; Zhou, Y. Z.; Han, Y. Y.; Wu, F. W.; Qi, B. F. Can J. Chem. 1986, 64, 837-839. (5) In the previous study, serratinine (4) and serratanine A have been isolated as major alkaloids from L. serratum var. serratum: (a) Ishii, H.; Yasui, B.; Nishino, R.; Harayama, T.; Inub...

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ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

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