Lactone protoanemonin

N.A. Lactone, protoanemonin, anemonin, pulsatoside, anemonol." Antibacterial, as an irritant. 

N.A. Anemone hepatica (DC.) Ker-Gawl. A. patens L. A. pulsutilla L. Lactone protoanemonin (anemonin), triterpenoid saponins, tannins, volatile oil." For cramps, menstrual problems, distress, spasmodic pain of the reproductive system. 

Lactones. Physiologically active lactones such as parasorbic acid, coumarin, scopoletin, and protoanemonin occur in many plant families (Figure 2). The lactones may perform a regulatory function in the plant, and have been shown to inhibit germination and to repress root growth [reviewed in detail by Hemberg 61), Evenari 36,37), and Borner 12)]. 

In addition to effects on biochemical reactions, the inhibitors may influence the permeability of the various cellular membranes and through physical and chemical effects may alter the structure of other subcellular structures such as proteins, nucleic acid, and spindle fibers. Unfortunately, few definite examples can be listed. The action of colchicine and podophyllin in interfering with cell division is well known. The effect of various lactones (coumarin, parasorbic acid, and protoanemonin) on mitotic activity was discussed above. Disturbances to cytoplasmic and vacuolar structure, and the morphology of mitochondria imposed by protoanemonin, were also mentioned. Interference with protein configuration and loss of biological activity was attributed to incorporation of azetidine-2-carboxylic acid into mung bean protein in place of proline. 

A highly reactive natural product which contains such a geminally donor-acceptor substituted alkene is protoanemonin (Scheme 3.12), a toxic, skin-irritating lactone produced by various plants (ranunculaceae). The natural precursor to this compound is the glucoside ranunculin [44, 45], which yields protoanemonin enzymatically on maceration of plant tissue. Protoanemonin is unstable and quickly polymerizes or dimerizes to the less toxic anemonin. 

Protoanemonin. S-Methylene-2(SH)-furanone 4-hydroxy-2,4-pentadienoic acid y -lactone 5-methylene-2-... 

I penicillic acid, protoanemonin, angelica lactone, digitoxine... 

Eisner, U., J. A. Elvidge, and R. P. Linstead Unsaturated Lactones and Related Substances. Part V. Dihydro-p-ketomuconic Acid and Carboxy-lactones of the Protoanemonin Type. J. Chem. Soc. (London) 1501 (1951). 

The utility of y-alkylidenebutenolides is demonstrated in both intra- and inter-molecular [Rh2(OAc)4l-catalysed 1,3-dipolar cycloaddition reactions in CH2CI2 affording spiro[6,4]lactone moieties with the concomitant constmction of quaternary Spiro stereocentres. Furthermore, a convergent and versatile route for the formation of the (5,7) skeleton of molecules, isolated from the Schisandra genus, is reported. Computational studies provided the mechanism of the intermolecular [3 + 2]-cycloaddition between 2-diazo-l,3-ketoester and protoanemonin and rationalized the empirical observations. " ... 

Ptotoanemonin The glycoside lanunculin yields a lactone known as protoanemonin upon hydrolysis. Protoanemonin is a volatile yellow oil that combnes with sulfhydryl groups and produces a strong vesicant and irritant action on skin and mucous mernbranes. 

Coriamycin (30) is a member of the picrotoxane sesquiterpenes it stimulates the central nervous system, similar to the activity of the better known picro-toxinin. In a general route for the construction of the picrotoxane carbon skeleton, Tanaka et al have described a stereocontrolled synthesis of (30), starting from the product (26) resulting from l,6>addition of 2-methylcyclopentane-l,3-dione to protoanemonin (25). Methanolysis of (26) led to (27), which was converted into (28) by addition of isopropenylmagnesium bromide. The latter was then converted into coriamycin (30) via the intermediate lactone (29). 

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