Ochrosia oppositifolia

Recently three new derivatives of 18,19-dihydrocorynantheol (21) have been isolated from natural sources. 10-Hydroxydihydrocorynantheol (22) has been found in Ochrosia moorei F. Muell. (26), and its structure has been determined by chemical analysis and by IR, H-NMR, and mass spectra. Ochropposinine (23) was isolated first in 1972 from Ochrosia oppositifolia K. Schum. (27, 28) and recently from Ochrosia moorei (26) by Potier s group. The relative configuration of C-20 as well as the absolute configuration of 23 have been elucidated. Ochromianine (24) isolated from Ochrosia miana H.Bn. ex Guill. (29) could be described very probably as 1 l-methoxycorynan-17-ol. The relative configuration of C-20 has not as yet been determined exactly. 

Neisosperma oppositifolia (Lam.) Fosberg Sachet, (syn Ochrosia oppositifolia) [Apocynaceae]... 

The leaves of Ochrosia oppositifolia contain two new alkaloids, 10-hydr-oxyapparicine (169) and 10-methoxyapparicine (170), whose overall structures became clear from examination of their mass and 300 MHz n.m.r. spectra. The position of the aromatic substituent in (170), which could not be deduced from the spectroscopic data, follows from the typical 5-methoxyindole u.v. absorption of the secondary base (171) and it Nb-acetyl derivative (172), produced by saturation of the 16,17 and 19,20 double-bonds in 10-methoxyapparicine and simultaneous hydrogenolysis of the benzylic 6-Nb bond. Methylation of the second, amorphous alkaloid with diazomethane gave (170) consequently it is 10-hydr-oxyapparicine (169). 

Ochrolifuanines A and B (103b) from Ochrosia lifuania and O. oppositifolia are stereoisomers of the same structural type. 

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