Lythraceae alkaloid simple quinolizidine

Simple quinolizidine alkaloids of the Lythraceae, "which include the well-known natural products (2S,4S,9aR)-(—)-lasubine I (1341) and (2S,4S,9aS)-(—)-lasubine II (1342) and substituted cinnamate esters thereof such as subcosines I and II, (1343) and (1344), are less common than those in which the quinolizidine forms part of a macroHde or cyclophane system containing a biaryl component (Figure 32). Since the macrocychc alkaloids are not pertinent to this review, they will not—with one exception—be discussed further vide infra). 

Figure 32 Simple quinolizidine alkaloids of the Lythraceae (-)-lasubine I (1341) —)-lasubine II (1342) (+)-subcosine I (1343) (+)-subcosine II (1344) (+)-sarusubine A (1347).

Alkaloids of the family Lythraceae were reviewed in Volumes 18 and 35 of this series (595, S). The latter review, published in 1989, was devoted to developments during the period 1979-1987, and overtyped to some extent with the review on simple indolizidine and quinolizidine alkaloids in Volume 28 (1). Also worth noting is a phytochemical and phytopharmacological review on the New World flowering shrub Heimia salicifolia, an important source of these alkaloids (596). 

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