Arthur, H. R. published the artcileExamination of the Rutaceae of Hong Kong. I. Flavonold glycosides from Zanthoxylum species and the occurrence of optically active hesperetin, Synthetic Route of 69097-99-0, the publication is Journal of the Chemical Society (1956), 632-5, database is CAplus.
The barks of Zanthoxylum species of Hong Kong contained hesperidin (I) and diosmin (II). Hydrolysis of I yielded a mixture of (±)- (III) and (-)-hesperetin (IV) from which pure III and IV were isolated. III and IV were characterized, and IV was racemized. III was converted into diosmetin (V) with N-bromosuccinimide. It was coneluded that I was a β-7-rutinoside of IV. Dried bark (400) g.) of Z. avicennae extracted with refluxing MeOH; and the extract concentrated gave 2.4 g. solids; the filtrate on further concentration yielded 1.5 g. brown crystals. The first crop extracted with light petroleum and then with MeOH and the residue crystallized gave II hydrate, m. 280° (decomposition) (from 50% aqueous C5H5N). The 2nd crop similarly treated yielded I hydrate, m. 260° (decomposition), [α]D27 -88.2° (c 1.24, C5H5N), and some more II hydrate. II (5 g.) left 4 days at room temperature with Ac2O-C5H5N, and the product crystallized from alc. and refluxed 2 hrs. with 5 ml. H2SO4 and 95 ml. alc. gave V, m. 253.0-4.5° (from alc.); triacetate, m. 189-91°; both compounds gave a red test with Mg-HCl-MeOH. V was also prepared from the hydrolysis of II in (CH2OH)2 by the method used for the hydrolysis of I. I (10 g.) refluxed 2 hrs. with 6% NaOH yielded isoferulic acid, m. 228-9°, pos. test with FeCl3; acetate, m. 204-5°. I (5 g.) treated at room temperature with Ac2O-C5H5N gave the acetate, C44H50O23, m. 176-9° (from alc.). I (5 g.) and 100 ml. (CH2OH)2 containing 5 ml. concentrated H2SO4 treated 40 min. in the H2O bath gave 1.8 g. of a mixture of III and IV, m. 224-6°, [α]D26 -16.9° (c 1.42, EtOH). I (4 g.), hydrolyzed by refluxing in dilute H2SO4 20 hrs., gave a mixture of III and IV, and from the filtrate glucose and rhamnose were isolated and identiffed as their osazones. The mixture (20 g.) of III and IV fractionally crystallized from EtOH by the triangular scheme gave 2.2 g. III as hexagonal prisms, m. 226-8°, [α]D27 0.0° (c 1.56, EtOH), and 2.5 g. IV as the more-soluble fraction, triangular plates, m. 216-18°, [α]D27 -37.6° (c 1.80, EtOH). The following III derivatives were prepared: 4′,7-di-Me ether, m. 132-3°; oxime, m. 227-8° (decomposition); triacetate, m. 139-41°. IV derivatives 4′,7-di-Me ether, m. 149-51° [α]D28 -35.6° (c 1.04, CHCl3); oxime, m. 219-20° (decomposition), [α]D27 -16.1° (c 0.40, EtOH); triacetate, m. 130-2°, [α]D26 21.1° (c 1.28, CHCl3). III and IV and their derivatives gave a red solution with Mg-HCl-MeOH. IV (0.4 g.) in 5 ml. (CH2OH)2 heated 2 hrs. at 250-60° in a sealed tube gave 0.1 g. III. Solutions of IV left 3 days in EtOH-NaOH or Et-OH-HCl did not racemize. III triacetate (0.9 g.), 0.45 g. N-bromosuccinimide, and 0.05 g. Bz2O2 heated 1 hr., 0.3 g. more N-bromosuccinimide added, the succinimide recovered the next morning, the filtrate concentrated, and the residue washed with hot H2O and crystallized gave 0.08 g. V, m. and mixed m.p. 250-3°. The dried bark of Z. cuspidatum gave I hydrate. II was isolated from the root bark of Z. nitidum. I and II were not isolated from the bark of the last species.
Journal of the Chemical Society published new progress about 69097-99-0. 69097-99-0 belongs to tetrahydropyran, auxiliary class Other Aliphatic Heterocyclic,Benzene,Phenol,Ether,Inhibitor, name is 5,7-Dihydroxy-2-(3-hydroxy-4-methoxyphenyl)chroman-4-one, and the molecular formula is C16H14O6, Synthetic Route of 69097-99-0.
Referemce:
https://en.wikipedia.org/wiki/Tetrahydropyran,
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