152 



there are four sapogcnins which are 

 used for progesterone synthesis. One 

 of tliese, diosgcnin from the "old" bo- 

 tanical drug Dioscorca, Mexican Yam, 

 is most useful in this respect. From this 

 finding one is set to speculating 

 whether the natives of Mexico, Central 

 America, and Africa, where most of 

 these plants grow, weren't correct after 

 all centuries ago in attributing con- 

 siderable benefits to certain yam roots 

 and Strophanthus fruits in the treat- 

 ment of adrenal hormone and corpus 

 lutcum deficiency diseases. 



Alkaloids.— In the realm of alka- 

 loids that can be separated from plants 

 there are many examples of new drugs 

 prepared by chemical modification of 

 existing molecules. This has been es- 

 pecially true among certain tropane 

 types, for example the cocaine, atropine 

 and ergot alkaloids. 



Ergot alkaloids, for example, ergo- 

 novine, have been the chief chemical 

 sources for the synthesis (and probably 

 biosynthesis) of an indole acid known 

 as lysergic acid, Tliis acid is found in 

 the crude drug but it has had only 

 academic interest up until a few years 

 ago. An amide derivative, known as 

 hsergic acid dieth}lamide has been 

 prepared from lysergic acid and this 

 derivative has been shown to have 

 marked stimulating and, later, depres- 

 sant effects on the higher brain centers. 

 Visual perception is greatly altered and 

 marked hallucinations occur. More im- 

 portant, however, is the depressant ef- 



LOWER PLANTS, DISEASES, AND MEDICINE 



feet of this drug on the mind. Humans 

 are reported to respond as though in a 

 hypnotized state and to reveal events 

 which might otherwise be retained as 

 guarded secrets. Human subjects are 

 reduced mentally to placid followers 

 of the slightest persuasion. The mili- 

 tary applications of such a compound 

 are far-reaching. There are strong indi- 

 cations that lysergic acid diethylamide 

 (LSD-25) has already been put to 

 military and political use by some for- 

 eign nations. 



Conclusion— Plant cells fundamen- 

 tally are chemical factories and many 

 possess a rich supply of therapeutically 

 useful constituents. As long as man is 

 driven to seek better medicines, par- 

 ticularly those which have selective 

 actions, he will explore the laboratories 

 of nature. With the improved tech- 

 niques at his command today it is 

 likely that new drugs will continuously 

 emerge from plants. Many of these will 

 be the result of the re-investigations of 

 older botanicals and the clues for pur- 

 suing such investigations will fre- 

 quently come from a more careful at- 

 tention to the history of botany in 

 medicine and to the customs and folk- 

 lore remedies of bygone generations. 

 Other new drugs will come from the 

 great efforts of the chemist who seeks 

 by application of the simple and most 

 complex rules of organic chemistry to 

 modify the products of nature in order 

 to suit his objectives in medicinal 

 chemistry. 



QUESTIONS 



1. What contribution did Dioscorides 

 make to medicine and for how long 

 did his influence extend? 



5. What was the relationship of the an- 

 cient Chinese to antibiotics? Discuss 

 modern antibiotics. 



2. What profession ser\cs as the closest g Discuss the history and uses of Rau- 

 link between botany and medicine? wolfia. 



3. Describe the field of pharmacognosy. ^ ^^^^^^ ^^^^ interesting uses does the 



4. Who was Paul Ehrlich and what was Aloe plant have? 

 his connection to chemotherapy? 



