Monographs Details: Strychnos diaboli Sandwith
Authority: Krukoff, Boris A. 1965. Supplementary notes on the American species of Strychnos VII. Mem. New York Bot. Gard. 12: 1-94.
Family:Loganiaceae
Description:Distribution and Ecology - British Guiana: basin of Rio Mazaruni, Forest Dept. 2297 (K).Distribution: Well distributed in British Guiana (basins of the Essequibo, Pomeroon, Mazaruni and Demerara Rivers). Its distribution in Brazil will be discussed in the next supplement which is now in process of preparation.

Discussion:This plant is of historical interest. In 1931 N. Y. Sand with described this species as new (Kew Bull. 1931: 486. 1931) and he also published its beautiful illustration (Hook. Ic. pl. 3173. 1932). A few years later Dr. H. King isolated a pure crystalline alkaloid, diaboline, from an authentic sample of its stem bark, the first alkaloid of the American species of Strychnos to be isolated and not considering the alkaloids isolated from various curares. His collaborator, pharmacologist Dr. Ranyard West, made pharmacological tests with this new crystalline alkaloid. Papers by King and West attracted considerable attention of chemists and pharmacologists, including those of Merck Research Laboratories (Drs. R. Major and H. Molitor). As a result, on June 10, 1935 I was given a commission by Merck Research Laboratories to investigate and obtain authentic materials of plants entering the curare of the Tecuna Indians of Brazil which culminated in the publishing, together with J. Monachino, of a monograph of the American Species of Strychnos in Sept. 1942. Ten additional short papers were published from 1943 to 1950, although for all practical purposes my work on Strychnos was abruptly terminated on Nov. 27 1948 with my departure for Guatemala. The intensive search for Strychnos, unequalled for any group of plants in the great basin of the Amazon (except for Hevea during the war), continued uninterruptedly from 1942 to 1960. About fifteen hundred new collections were made and they were largely collected by several persons (Froes, Ducke, Black and others), all associated with the Instituto Agronômico do Norte (Para, Brazil), by R. E. Schultes who, over a period of several years, has made rather extensive collections in the Amazonian Colombia, and by others. Since our revision of the American species of Strychnos was published in 1942, two new species (S. Duckei in 1946 and S. Torresiana in 1948) were described by us; one species (S. eugeniaefolia in 1953) by Monachino; four species (S. pachycarpa in 1945; S. Krukoffiana in 1947; S. Blackii in 1950 and S. Froesii in 1951) by Ducke; one species (S. oiapocensis in 1959) by Froes; one species (S. malacosperma in 1955) by Ducke and Froes; one species (S. Bovetiana in 1960) by Pires and three new species are described in this paper. In his paper “O gênero Strychnos no Brazil” (31) published in 1955, Ducke made a valuable contribution by describing mature fruits and seeds of all known Brazilian species except for S. asperula, S. Krukoffiana, S. xinguensis, S. solimoesana, S. Smithiana, S. Duckei, S. Bovetiana, S. albiflora, S. Schultesiana, S. oiapocensis and S. pedunculata. It is incredible but it is a fact that of the 64 species (and one variety) of known American species of Strychnos 50 species (and one variety) are known from collections in flower and fruit; 11 species from collections in flower only (fruits are not known of S. colombiensis, S. asperula, S. Krukoffiana, S. xinguensis, S. solimoesana, S. lobelioides, S. Smithiana, S. Duckei, S. Bovetiana, S. albiflora, and S. oiapocensis; only immature fruits are known of S. pedunculata) and two species from collections in fruit only (flowers are not known of S. eugeniaefolia and S. Schultesiana. These statistics are very different, to say the least, from the statistics of specimens available to N. Y. Sandwith in 1933 when he was engaged in the difficult pioneering task of bringing order in the species of Strychnos occurring in British Guiana and Trinidad. Equally dynamic progress was made since the late thirties in the chemistry of Strychnos species and of various curares, largely through the efforts of King and West, of H. Wieland and his coworkers, of the Nobel Laureate Karrer, Schmid and their coworkers, of Schlittler and his coworkers, of Marini-Bettolo and his collaborator, Nobel Laureate Bovet and their coworkers, of T. Wieland and his coworkers, and Battersby and his coworkers. Inasmuch as I have been very closely in touch with developments in the progress with American species of Strychnos since 1936, I believe that it is quite correct to say that it all started with N. Y. Sandwith’s brief paper in which he described S. diaboli, and King and West’s work on its bark. Fanshawe (34: 65) gives the following information on the local names, on the field characters of this bush-rope, on its distribution in British Guiana and on its alkaloids, probably on the authority of Dr. King: “Local names: Black devildoer; kwabanaro (Arawak); urariballi (Arawak); kumarawa (Akawaio, Arekuna, Patamona, Macushi). “A canopy climber, to 6 inches in diameter; bark rough, dark reddish-brown; slash pale crimson, hard, brittle and thin. “It occurs in mora and rain-forest of all types from lateritic hill-tops to clay land in the North Central district; occasional to frequent. “It yields a weak alkaloid, diaboline, with an interesting mixture of the actions of strychnine (stimulation of the central nervous system) and curarine (depression of nerve-muscle conduction). King states that he found no curare-like action. It has a lissive action on dogs.” As per King, the alkaloid content of this species was found to be “++” (Forest Dept. 2295) (74). In another paper by the same author (75), the alkaloid content is given as “+ to + +,” curare activity “none” (Forest Dept. 2295, 2468 and 2473). They are from British Guiana. It is not known which part of the plant was used for this work, presumably stem bark. In the second paper the author states: “S. diaboli yields a crystalline water soluble alkaloid diaboline with the formula C21H26O3N3” This species was studied by Schlittler and his coworkers (85) who isolated diaboline and desacetyldiaboline from stem bark collected by Fanshawe in British Guiana. The structure of diaboline was studied by Battersby and Hodson (111). The work of Marini-Bettolo, Bovet and their coworkers on the samples from Brazil will be discussed in the next supplement. Recently I received a very interesting letter from Dr. Ranyard West dated March 23, 1964 which concerns the pharmacological actions of various extracts of three species of Strychnos and of Guettarda acreana, and which I will quote below: “When I come to go into the Strychnos situation I am impressed with two things. The first is the large number of alkaloids isolated from plants like S. Melinoniana and S. toxifera by the modem techniques. And the second is the real dearth of pharmacology since the ’30s. “The following plants: S. Erichsonii, S. diaboli, Guettarda acreana, S. “2482”* (total alkd.) (non-quat. alkd. (total alkd.) (non-quat. alkd.) inch diaboline) were found by me to have: 1. curarising 2. nicotine-like 3. central nervous excitant 4. limited “lissive” actions. “I do not know whether the shape of your present paper allows you to mention these pharmacological actions. I mention this because I see that, for some reason or other, King did not attach the full pharmacology (as above) to his report on diaboline in 1949” (74). “Probably this was because the pharmacologists who worked with him after my time only tested for the classical paralysing (“curari-form”) action, in which diaboline is undoubtedly weak. But its actions considered in toto linked it to strychnine on the one hand and ‘curarisation’ on the other (see my paper of 1937)” (77) “which is just the arrangement which is set out, chemically, by Karrer and Schmid today in their scheme: Strychnine—Wieland-Gumlich aldehyde—diaboline—toxiferine Why I am so anxious to see the relationship of chemistry to total pharmacology made clear by exhibiting the early pharmacology is that my own hope is that it will be within this scale of linked chemistry and mixed pharmacological action that what we searched for as the lissive action of curare will eventually make itself apparent. It is for this reason also that I would wish to see as many as possible of these new alkaloids tested in these earlier ways of ours.” The lissive action of curare is well reviewed in A. R. McIntyre’s book “Curare,” although his reference 23 at p. 176 should be to “Curare in Man,” Proc. Roy. Soc. Med. 25, 1107-1116 where the term “lissive” was first used by Dr. West. I am in complete agreement with Dr. West that the time is now ripe to search for this activity again. Many new alkaloids were isolated in pure form from various species of the American Strychnos since the early ’30s. Once the very interesting and elusive “lissive” action is traced to some definite pure alkaloid, then this will open a new field for further investigation.
Distribution:Guyana South America| Brazil South America|