Constituents of Domestic Citrus Plants. Part XXIII. Citbismine-A, -B and -C, New Binary Acridone Alkaloids from Citrus Plants.

.ALPHA.-Glucosidase Inhibitory and Antioxidant Acridone Alkaloids from the Stem Bark of Oriciopsis glaberrima ENGL. (Rutaceae)

“…The 1 H-, 13 C-NMR and MS parameters of the known compounds were consistent with those reported in the literature.…”

“…4) In this paper, we report the isolation and the structural elucidation of four new acridones designated as oriciacridone C, D, E and F, and their biological activities. We also present the 13 C values and biological activity of synthetically known acridone 1,3,5-trihydroxy-4-prenylacridone. 5) Air-dried, ground stem bark of O. glaberrima was extracted with a mixture of CH 2 Cl 2 -MeOH (1/1) at room temperature.…”

“…10) On the other hand, the HMBC cross-peak between the proton H-7 (d 7.10) and carbon signals at C-5 (d 146.4) and C-8a (d 121.7) indicated that the second hydroxyl group was located at the C-5 position. From the above spectroscopic studies, the structure of oriciacridone C (1) was assigned as (ϩ)-1,5-dihydroxy-2-isopropenyldihydrofuran [3,4- 13 C-NMR (Table 1) suggested that compound 2 was a position isomer of oriciacridone C (1). Except an isolated aromatic proton shifted to d 6,21 ppm, other signals in 1 H-NMR spectrum were closely similar to those of compound 1.…”

Quinoline, quinazoline and acridone alkaloids

“…The thirteen new acridone alkaloids reported during the review period, all from plants belonging to the Rutaceae, are listed in Table 3 along with known alkaloids from new plant sources. 11,14,[68][69][70][71][72][73] 1,3,5-Trihydroxy-2,4-diprenylacridone alkaloids, hitherto found almost exclusively in the genera Atalantia and Citrus, have now been isolated from the taxonomically distant plant Bosistoa transversa. 68 Leaf and bark material of this previously unexplored Australian tree yielded several known acridone alkaloids of the type under discussion, including N-methylatalaphylline 119, N-methylatalaphyllinine 120 and yukocitrine 121, as well as the three new compounds bosistidine 122, bosistine 123 and the yukocitrine derivative 124.…”

Cytotoxic activity of dimeric acridone alkaloids derived from Citrus plants towards human leukaemia HL-60 cells

“…We isolated and elucidated the structure of six novel acridone dimers from the roots of Marsh grapefruit (Citrus paradisi Macf.) [3][4][5][6] and these include: citbismine-A (1), citbismine-B (2), citbismine-C (3), citbismine-D (4), citbismine-E (5) and citbismine-F (6). A few of the monomeric acridone alkaloids displayed a variety of biological activities, such as cytotoxicity [7][8][9] and antiviral [10] and antimalarial activity.…”