Echinocystis macrocarpa

Alkaloids (pyrazolinc derivatives) and some others of undetermined structure have been reported from several genera. The family is known chemically for the cucurbitacins-loxic steroidal substances. In this study, 106 samples in 73 species were tested two were already known to contain alkaloids, Momordica charantia (2/11) and M. foeiida (1/2). Other positives included Coccinea addensis (1/3), Cucumis anguria, C. zeyheri, Cucurbita foelidissi-ma (2/3), Echinocystis macrocarpa, Marah macrocarpa, Melothria cordala, Momordica cissoides, M. repens (1/2), Peponium macke-nii, Trichosanthes sp. 

Both the endosperm and cotyledons of the wild cucumber, Echinocystis macrocarpa Greene, have been shown to contain gibberellin-like substances. The... 

Echinocystis macrocarpa seeds, transhydrogenase of, 66 Electro mechanochemical model, transhydrogenase, 75... 

A useful method has been developed for converting the readily accessible 3-hydroxy-gibberellins into 2-hydroxy-gibberellins and it has been applied to the partial synthesis of two new gibberellins, A46 (74), isolated from Echinocystis macrocarpa (Cucurbitaceae), and A47 (75), isolated from the fungus Gibberella... 

Echinocystis macrocarpa green endosperm Microsomes Kau l6-ene Kaurenol 23)... 

Fig. 3.24 A and B. Changes in gibberellin content during seed development. (A) Echinocystis macrocarpa. After Corcoran and Phinney, 1962 [42]. (B) Hordeum vulgare cv. Brevia. After Mounla and Michael, 1973 [130]. — free gibberellin, bound gibberellin...

At first glance, it is difficult to recognize the gibberellins as diter-penes. However, any element of doubt about this has been dispelled by isotope experiments in vivo and in a cell-free system. In the fluid endosperm of the wild cucumber Echinocystis macrocarpa the following synthetic pathway has been demonstrated (Fig. 85) geranylgeranyl pyrophosphate—(—) kaurene—(—) kauren-19-ol —gibberellin A5. Presumably the synthesis then proceeds via Aj to gibberellic acid. 

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