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Hydrogen Cyanide Chemistry Synthesis of Diiminosuccinonitrile.

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Experimental:
A solution of 6-keto acid (0.1 mol) in xylene (500 ml) is
heated to boiling under reflux in a two-necked flask
fitted with reflux condenser and dropping funnel. Hydrazine
(0.11 mol) is then added and the mixture heated under
reflux for 4-5 hours, after which time the water is distilled
off as xylene/H,O azeotrope. The solvent is removed by
evaporation under vacuum and the residue taken up in
chloroform. The chloroform phase is washed twice
with 10% KHCO, solution, then with water, and finally
dried over MgSO,. After removal of solvent, the residue
is purified by distillation, recrystallization or chromatography.
Received: October 4,1971 [Z 536 IE]
German version: Angew. Chem. 84,153 (1972).
C O N F E R E N C E REPORTS
Comparative Studies of the Topography of the
Membranes of Mitochondria and Chloroplasts
Hydrogen Cyanide Chemistry:
Synthesis of Diiminosuccinonitrile['I
By Giinter Hauska"'
By Owen W Webster"]
The low temperature, base-catalyzed addition of hydrogen
cyanide to cyanogen gives diiminosuccinonitrile ( I ) in
high yield.
In Rocker's laboratory at Cornell University, U.S.A. the
reconstitution, from its component parts, of the respiratory
chain of mitochondria from succinate to oxygen has been
achieved (see"]). However, it was disappointing that the
energy in this artificial electron transport system could
not be obtained in chemical form as ATP. Evidently, a
specific arrangement of the components in the membrane is
necessary for ATP synthesis which is coupled to the
electron flux. This topography must be known precisely
before one can contemplate the construction of a "synthetic
mitochondrion" which might possibly lead to the
elucidation of one of the most important energy transformations in nature.
Diiminosuccinonitrile ( I ) is a white, crystalline, air-stable
solid that is readily reduced to diaminomaleonitrile (Z),
the well-known HCN tetramer. ( I ) forms oxalyl cyanide
The fact that both surfaces of the membrane can be made
accessible was a great help in Racker's investigations"!
In isolated mitochondria the surface which carries the
coupling factor 1 (Fl, a reversible ATPase) is on the
inside directed towards the matrix, whereas membrane
vesicles obtained after ultrasonic treatment have this
coupling factor outside, accessible from the medium.
These two surfaces have been studied systematically.
For example, attempts were made to strip components
from the surface without disrupting the membrane
structure and then to reattach them. Further, the reaction
of the bound components with hydrolytic enzymes, with
radioactive, impermeable reagents and, finally, with antibodies was investigated.
(I)
f
2 TosOH-H~O
o*
/p
pc,
NC
(3)
CN
( 3 ) on controlled hydrolysis, adds to electron-rich olefins
like ( 4 ) to give dicyanotetrahydropyrazines,and reacts
with ketones such as acetone to produce dicyanoisoimidazoles.
Lecture at Freiburg on October 18, 1971 [VB 331 IE]
German version: Angew. Chem. 84,173 (1972)
The membrane of the chloroplast is similar to the
mitochondria1 membrane in structure and function (in
[*] Dr. 0. W. Webster
E. 1. Du Pont de Nemours and Company,
Central Research Department, Experimental Station
Wilmington, Delaware 19898 (USA)
[I]R. W Begland, A. Cairncross, D. S. Donald, D. R. Hartter, W A.
Sheppard, and 0. W Webster, J. Amer. Chem. SOC. 93,4953 (1971).
Angew. Chem. internat. Edit. 1 Vol. I1 (1972)
The results so far can be summarized in a model (Fig. 1).
The coupling factors F, to F, and succinate dehydrogenase
(SDH) are accessible from the M-side (M for matrix).
The C-side bears the cytochromes c and cl. Cytochrome c
oxidase (a,a,) is accessible from both sides. It was assumed
that cytochrome b and ubiquinone (Q) extend through
the membrane. Protons are pumped from the M- to the
C-side when the membrane is excited. Both succinate
oxidation and oxygen reduction occur on the M-side
(Fig. 1).
1 No. 2
[*I
Dr. G. Hauska
Abteilung fur Biologie, Lehrstuhl fur Biochemie der Pflanzen
der Universitat Bochum
463 Bochum-Querenburg, Postfach 2148 (Germany)
153
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chemistry, hydrogen, cyanide, synthesis, diiminosuccinonitrile
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