ZIZYPHINE E

Description

An amorphous peptide alkaloid, zizyphine E has also been isolated from the root bark of Zizyphus oenoplea. It has specific rotations of [α]²⁰_D + 150° ± 2° (c 0.10, CHC13) and [α]²⁰_D - 111° ± 2° (c 0.10, MeOH). The ultraviolet spectrum in methanol has a single absorption maximum at 279 nm. Like the preceding base, the N-acetyl derivative has been prepared as a microcrystalline powder from MeOH-H20, m.p. 155°C. It has specific rotations of [α]²⁰_D + 55° ± 1° (c 0.10, CHC13) and [α]²⁰_D - 201 ° ± 3° (c 0.10, MeOH). The O,N-diacetyl derivative forms hexagonal bipyramids and needles when crystallized from MeOH-H20 which sublime above 270°C to give fine needles with m.p. > 350°C.

References

Cassells et at., Tetrahedron, 30, 2461 (1974)