Simple indole alkaloids and those with a nonrearranged monoterpenoid unit

The class of steroid-like compounds designated cardiac glycosides includes well-known drugs such as digoxin, digitoxin, and ouabain. Their continued efficacy in treatment of congestive heart failure and as anti-arrhythmic agents is well appreciated. Less well known, however, is the emerging role of this category of compounds in the prevention and/or treatment of proliferative diseases such as cancer. New findings within the past five years have revealed these compounds to be involved in complex cell-signal transduction mechanisms, resulting in selective control of human tumor but not normal cellular proliferation. As such, they represent a promising form of targeted cancer chemotherapy. New clinical studies of their anticancer potential as single or adjuvant treatments may provide insight into these potentially valuable therapeutic options. This review focuses on recent findings on cellular pharmacology of cardiac glycosides as they relate to treatment of human cancer and attempts to explain why these agents have been overlooked in the past.

Cardiac glycosides as novel cancer therapeutic agents

Asymmetric organocatalysis in total synthesis – a trial by fire

Natural and synthetic 2H-pyran-2-ones and their versatility in organic synthesis☆

Structure–cytotoxic activity relationship for the toad poison bufadienolides

Two new (2-phenylethyl)amine alkaloids, convolutamines F and G, and a dibromohydroxyoxindole alkaloid, convolutamydine E, have been isolated from the butan-1-ol soluble material of the Floridian marine bryozoan Amathia convoluta. Their structures were elucidated on the basis of spectroscopic data. Convolutamine F exhibited activity against KB, KB/VJ-300, and U937 cells. This compound also exhibited the inhibitory effects for cell division of fertilized sea urchin eggs.

Three new alkaloids, convolutamines F and G, and convolutamydine E, from the Floridian marine bryozoan Amathia convoluta

Bufobutanoic acid and bufopyramide, two new indole alkaloids from the Chinese traditional drug Ch'an Su

Conformational preference of two toad poison bufadienolides, bufarenogin and psi -bufarenogin

We have examined the column chromatography using hydrophobic gel carriers, Sephadex LH-20 and HP-Cellulofine, for separation of ten toad poison bufadienolides: resibufogenin, cinobufagin, bufalin, bufotalin, cinobufotalin, telocinobufagin, desacetyl-cinobufagin, desacetyl-bufotalin, desacetyl-cinobu-fotalin, and gamabufotalin (Figure 1). As a result, the use of developing solvents such as n-hexane/CH2Cl2/MeOH(4:5:1), n-hexane/CHCl3/MeOH(4:5:1), and n-hexane/toluene/ MeOH (3:2:1) provided the effective separation of bufadienolides. For separation, we have established the flow speed of developing solvents and the relationship of separation with the diameter and length of column, in addition to the comparison of separation by Sephadex LH-20 and HP-Cellulofine and the relationship with silica gel thin-layer chromatography. Also, we have tested the separability of hydrophobic gel by repeated use and the recovery of bufadienolides on hydrophobic gel column by repeated use. 10.1081/JLC-100101814-F0001 Figure 1. ...

Ayano Kotake

Papers

Structure–cytotoxic activity relationship for the toad poison bufadienolides

Three new alkaloids, convolutamines F and G, and convolutamydine E, from the Floridian marine bryozoan Amathia convoluta

Bufobutanoic acid and bufopyramide, two new indole alkaloids from the Chinese traditional drug Ch'an Su

Conformational preference of two toad poison bufadienolides, bufarenogin and psi -bufarenogin

Separation of toad poison bufadienolides by hydrophobic gel