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Breynia officinalis (Euphorbiaceae) is a poisonous perennial shrub 1.5-4 m in height, and grows in Okinawa, Taiwan, and southern China. However, it is used as a remedy for healing wounds and edema, as an ointment, and for syphilis and intestinal hemorrhage due to overwork by oral administration.1) Continuing our survey of Okinawan resource plants, the constituents of B. officinalis were investigated.From a n-BuOH-soluble fraction of the MeOH extract of the leaves of B. officinalis, 12 compounds were isolated. Five (1-5) were found to be megastigmane glucosides, one (1) of which was a known compound, identified as turpinionoside B.2) The other known compound, betulalbuside A (6) is 3,7-dimethylocta-1,6-dien-3,8-diol 8-O-b-D-glucopyranosiode, of which absolute configuration at the 3-position was determined for the first time. The known phenolic glucosides (7-9) were identified as arbutin, 3) robustaside A, 4) and eximine, 5,6) respectively. New phenolic compounds 10-12 were also derivatives of arbutin, like compounds 8 and 9. This paper deals with the structural elucidation of the new compounds. Results and DiscussionCompounds 1-12 were isolated from the n-BuOH-soluble fraction of a MeOH extract of the leaves of B. officinalis by the combination of highly porous synthetic resin , and normal-and reversed-phase column chromatography (RPCC). Droplet counter-current chromatography (DCCC) and ODS-HPLC were also performed for the purification of the compounds. The details and yields are given in Experimental.Turpinionoside B (1) was isolated as an amorphous powder, and NMR spectra indicated the presence of a megastigmane skeleton and a glucopyranose unit. From spectroscopic data, including 1 H-and 13 C-NMR spectra, and [a] D the structure of 1 was determined to be (3S,5R,6S,9S)-megastigman-7-ene-3,6,9-triol 9-O-b-D-glucopyranoside. 2)Breyniaionoside A (2), [a] D Ϫ48.8°, was isolated as an amorphous powder and its elemental composition was determined to be C 19 H 32 O 9 using negative-ion high-resolution (HR) FAB-MS. The IR spectrum of 2 showed a strong absorption band at 3376 cm Ϫ1 suggestive of a glycosidic structure. The 1 H-and 13 C-NMR spectra showed signals attributable to a glucopyranosyl unit, and 13 carbon signals, which included two tertiary methyls at the geminal position, one secondary methyl, two methylenes, one methine, one quarternary carbon, one primary, secondary and tertiary carbinol, respectively, one disubstituted trans double bond, and a ketone functional group. The 1 H-1 H correlation spectroscopy (COSY) spectrum showed series correlations from H-7 (d H 5.95), H-8 (d H 5.75), and H-9 (d H 4.47) to H 2 -10 (d H 3.62). These data indicated that this aglycone is a derivative of megastigmane, of which the 10-methyl was oxidized to a primary carbinol. The secondary methyl on the ring had the equatorial orientation, since H-4 (d H 2.46) appeared as a triplet signal (Jϭ13 Hz), and the side chain at the 6-position was in the equatorial orientation, as judged from the phasesensitive nuclear Overhauser enhanc...

Abstract. Real-time interactive virtual classroom with tele-education experience is an important type of distance learning, while the current available systems are not able to connect different classrooms in open network for intercontinental and intercultural learning. Open Smart Classroom, which is an upgrade learning system based on Smart Classroom using Web Service technology, provides more extensible and scalable features to tackle the new requirements and challenges of distance learning. Open Smart Classroom is developed based on Open Smart Platform, the software computing infrastructure for Smart Space, which provide three new features: 1) open and standard interface for better mobile devices connection and communication without any prior configuration; 2) open services invocation channel between inside modules and outside systems 3) open network in which multiple Smart Spaces can connect and communicate with each other. Making use of these new features, Open Smart Classroom shows a novel and interesting experience to both of the teachers and students for intercultural and intercontinental distant learning, which also gives a significant research perspective of future distance blended learning system.

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