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Occurrence of Cyclododecasulfur in Sulfur Melts.

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band (cf. Table 2). This result is not intelligible within the
framework of the H M O theory.
Received: August 4th, 1967
[Z 607 lE]
G e r m a n version: Angew. Chen;. 79, 931 (1967)
[*I Priv.-Doz. Dr. H. Fischer and
W. D. Hell
Max-Planck-Institut ftir hledizinische Forschung,
Institut fur Chemie
Jahnstr. 29
69 Heidelberg (Germany)
[ l ] Part I1 of Interaction of Orthogonal jr-Electron Systems of
Cumulenes. - Part I: H . Fisclier and H. Fischer, Chem. Ber. 100,
755 (1967).
[2] H. Fischrr in S. Patai: The Chemistry o f the Alkenes. Wiley,
London 1964.
[3] R. Kuhn and H. Krauch, Chem. Ber. 88. 309 (1955); cf. also
F. Bohlmann and K. Kieslich, ibid. 88. 1211 (1955).
!4] D.Y.Curtin, r7. C. Tuires, and D . H. Dybvig, J . org. Chemistry
25, 1 5 5 (1960).
[ 5 ] G. E. Coafvs and I.. E. Surton, J. chem. SOL (London) 1942,
567.
[6] M . Sintonetto and S. Carra, Tetrahedron 19, pp. 2,467 (1962).
Chemical Shifts of NMR Signals of the Acetyl
Protons of 6-Penta-0-acetylglucose
By K. Heyns, W.-P.Trautweiii, and F. Garrido Espinow[*l
The N M R signals of the acetoxyl groups of acetylated carbohydrates are often used for configurational and conformational analysis[il, a use that depends on the fact that the
methyl protons of equatorial acetoxyl groups in general
absorb at higher field than do such axial groups. Whereas
this rule has proved its value for countless partially or
completely acetylated pyranoses [21, halogeno sugars 131,
amino hexoses 141, and inositols 151, there are only a few, and
partially contradictory, indications as to how to assign the
individual signals within each of these groups. It is sometimes
assumed that acetoxyl groups on the primary C atom 6 of
hexopyranoses absorb at highest field [L ,61 and that acetoxyl
groups above the plane of the ring are less shielded than those
under the pyranose ring[7,81.
We have studied, by N M R spectroscopy, 2,3,4,6-, 1,3,4,6-,
1,2,3,6-, and 1,2,3,4-tetra-O-acetyl-~-~-glucopyranose
that
have been acetylated on the unsubstituted O H group by
hexadeuterioacetic anhydride in pyridine. Whereas the N MR
spectrum of unlabeled 8-penta-0-acetylglucose shows four
Fig. 1. IH-NMR s p e c t r u m of 1,2,3,4-penta-U-acetyl-::-u-glucose at
100 M H z in CDCI,.
signals for the acetyl protons (one of these signals has double
intensity), the spectra of all the labeled compounds lack one
line, namely, that of the trideuterioacetyl group (Fig. 1). By
Angew. Chem. internat. Edit.
1 Vol. 6 /I9671 1 No. I I
selective labeling of individual acetyl groups it is possible to
assign each line in the spectrum to a definite acetyl group. It
was thus shown that the two signals at lowest field refer t o
groups o n C - l and C-6, whereas the line of relative intensity 2
is caused by the groups on C-2 and C-4; the signal a t highest
field was present in all the spectra and thus is to be ascribed
t o the group on C-3.
Received: August 4th, 1967
[Z 608 IE]
G e r m a n version: Angew. C h e m . 79, 937 (1967)
[*I Prof. Dr. K. Heyns, Dr. W.-P. TrdutWeln, and
Dr. F. Gariido Espinosa
Chemisches Staatsinstitut,
Institut fur Organische Chemie der Universitiit
Papendamm 6
2 Hamburg 1 3 (Germany)
111 L . D. Hall, Advances Carbohydrate Chem. 19. 51 (1964)
Bernsfein, and W. G.
[2] R. U . Lemierrx, R . K. Kiillnig, H. .I.
Schneider, 1. Arner. chem. SOC.80, 6098 (1958).
[3] D. Horfon and W. N . Turner, J . org. Chemistry 30, 3387
(1965); Chem. Commun. 1965, 113.
[4]D.Horton, W. E . Most, and K. D. Philips, J . org. Chemistry
32, 1471 (1967).
[ 5 ] F. W. Lichtenthnler, Chem. Ber. 96, 2047 (1963).
[6] f. C. Sowden, C. H. Bowers, I.. Hough, and S. H. Sliufe,
Chem. and lnd. 1962, 1827.
[73 K. Onodera, S. Hiram, F. M o ~ u d a and
,
N . Kashitviwa, J . org.
Chemistry 31, 2403 (1966).
[8] L. D . tIaN and I-. Hougli, Proc. chem. SOC.(London) 1962,
352.
Occurrence of Cyclododecasulfur in Sulfur Melts
B y M. Schniidt and H.-D. Block I*]
The physical properties of liquid sulfur have long been the
subject of studytll, but it was only the theoretical propositions by Powell and E y i n g [*], Gee [31, and in particular
Tobolskp and Eisenberg (41 that made it possible to interpret
satisfactorily its unusual behavior over the whole liquid
range. Fundamental to the theory that is currently recognized is the assumption of temperature-dependent equilibria
between cyclooctasulfur and catenaoctasulfur as “monomers” and of polycatenaoctasulfur as “polymer”.
We now report experiments which throw doubt on this
principle and at least necessitate refinement of, i f not a
change in, the theoretical interpretation. Working up sulfur
that has been melted at 120”C, 140”C, 165OC, 19OoC,
220°C, 29OoC, 340”C, 3SOoC, or 370°C and then brought
quickly to the solid state by cooling in air, cold water, or
liquid air leads in each case, reproducibly, t o crystalline
cyclododecasulfur~~l,
S12, even if only in a “yield” of cu.
0.1 ”/,. The sulfur used as starting material was free from
S12, as also from S6 and s g that are formed by chainbuilding on decomposition of thiosulfate by acid [ b l . Slow
cooling of the melt (during 10 hours) leads, however, to pure
s8. This result shows that in sulfur melts there are also Slz
rings in the equilibrium mixture alongside sg, and it is
certain that only a small part of the ,512 rings survive transition, on cooling, into the Ss rings that constitute the only
thermodynamically stable form. It is, however, also probable
that other, hitherto unisolated, rings S, ( x < 1 2 and in
particular x > 12 - perhaps even x 2- 12) are present in the
equilibrium of the melt, as previously postulated by Krebs 171.
It remains an open question to what extent the S12 content,
already shown to be present slightly above the melting
point, is responsible for the decrease of the “ideal” to the
“natural” melting point.
Experimental Example: 20 g of sulfur is heated at 200 “C for
10 min. The vessel is cooled with tap water and the sulfur is
divided as finely as possible and stirred for 1 2 hours with
955
100 ml of pure CS2 at room temperature. The clear yellow
solution, obtained by filtration from insoluble polymer, is
concentrated to 20 ml in a vacuum and then cooled at
-3OOC for 12 h. The mother liquor is decanted from precipitated sulfur, and the latter is treated dropwise, with
careful shaking, with sufficient pure CS2 (ca. 10 ml) to
dissolve all the yellow s8 and leave behind only the characteristic four-cornered platelets of S12. After decantation of
the solution, these platelets are washed with 1 ml of CS2 and
the remaining suspension of crystals is finally dried on filter
paper. In this way 20 mg of S12 (“yield” ca. 0.1 %) of Slz
is isolated, having m.p. 140-142’C (146-148 “C after
recrystallization from benzene).
Received: Auguat 2nd. 1967
[Z 610 IE]
German version: Angew. Chem. 79, 944 (1967)
[“I Prof. Dr. M. Schmidt and Dip].-Chem. H.-D. Block
Institut fur Anorganische Chemie der Universitat
Rontgenring I 1
87 Wurzburg (Germany)
[I] 1.A . Pulis and C. H. Mnssen in B. Meyer: Elemental Sulfur.
Wiley, New York 1965, p. 109--123.
[2] R. Poivell and H . Eyrinp, J. Arner. chem. SOC.65, 648 (1943).
[3] G. Gee, Trans. Faraday SOC.48, 515 (1952).
[4] A . V. Tobolsky and A. Eisenberg, J. Amer. chem. SOC.81, 780
(1959).
151 M . Schmidt and E. Wilheltn, Angew. Chem. 78, 1020 (1966);
Angew. Chem. internat. Edit. 5, 964 (1966).
[6] M . Schmidt and D . Block, unpublished.
[7] H. Krcbs in: Silicium, Schwefel, Phosphate. Colloquium der
Sektion fur Anorganische Chemie der IUPAC. Verlag Chemie,
Weinheim 1955, p. 113.
Photodimerization of Uracil Sensitized by Acetone
By C. H. Krauch, D . M. Kramer, P . Chandra, P. Mildner,
H . Feller, and A . Wackerc*l
When a 10-3 M solution of uracil in acetonelwater (1 : 3) is
irradiated with light of wavelength 315 nm (1x 106 erg/mm2),
four products are formed quantitatively, of which we have
identified one as the syn head-to-head dimer of uracil by
means of its RF value [I]. Use of more than 50 % acetone as
solvent during the irradiation leads to addition of about 5 %
of acetone. This photosensitized dimerization of uracil may
be more useful for molecular-biological studies than is the
dimerization by UV light [21, since in the latter the uracil also
adds water at the 5,6-double bondC31. When cytosine is
irradiated in aqueous acetone, a change in the molecule
(including addition of acetone) can be observed only after
radiation doses that have caused total reaction of uracil.
Acetone-sensitized photodimerization of thymine has already
been reported [41.
The effect of the reaction on the template activity of nucleic
acids is shown by the following observations. When poly-A,
poly-C, and poly-Ur5l (1 mg/ml) in 23 % acetone are irradiated with light of wavelength 315 nm (3x105 erg/mm2,
grating monochromator, Bausch and Lomb, Rochester,
USA; mercury high-pressure lamp HBO 200, Osram), the
extinction a t hmax falls by 1 % for poly-A, by 6 % for poly-C,
and by 61 % for poly-U. In cell-free protein synthesis (the
reaction mixture contained, after Nirenberg and Matthaei [61,
80 pg/ml of poly-U or 120 p.g/ml of poly-A or poly-C;
specific activity of the [14C]-amino acids = 3.6 mCi/mmole),
the irradiation affects only the phenylalanine incorporation
that is poly-U-dependent, this being inhibited to the extent
of more than 80%. If homopolynucleotides are used as
templates for the synthesis of R N A with a polymerase from
Micrococcus Iysodeikricirs~71,then again it is only the poly-Udependent incorporation of AMP that is inhibited (by
about 40 %). Thus photodimerization of uracil sensitized by
956
acetone provides a further, mild method of specifically
altering nucleic acids by photochemical methods.
Received: July 17th, 1967; revised: August 14th. 1967
[ Z 611 IE]
German version: Angew. Chem. 79, 944 (1967)
[*] Dr. C. H. Krauch
Mas-Planck-Institut fur Kohlenforschung
Abteilung Strdhlenchemie
Stiftstr. 34-36
433 Mulheim, Ruhr (Germany)
Dr. D. M. Kriimer, Dr. P. Chandra, Prof. Dr. P. Mildner,
Frau H. Feller, and Prof. Dr. A.Wacker
Institut fgr Therapeutische Biochemie der Universitat
Ludwig-Rehn-Str. 14
6 FrankfurtiMain (Germany)
[l] E. Fahr, G. Fiirst, G . Dorhofer, and H . Hoppe, Angew. Chem.
79, 235 (1967); Angew. Chem. internat. Edit. 6, 250 (1967).
[2] A . Wacker, L . Trager, and D . Weinblutn,Angew. Chem. 73,65
(1961).
131 R . L . Sinsfteimer and R. Hastinrs, Science 110, 525 (19491.
141 1. von Wilucki, H . Matthaus, and C. H. Krauch, Photochern.
and Photobiol. 6, 497 (1967).
[51 Poly-A = polyadenylic acid; poly-C = polycytidylic acid;
poly-U = polyuridylic acid.
[6] M . W . Nirenberg and J . H . Matthaei, Proc. Nat. Acad. Sci.
USA 47, 1588 (1961).
[7] C. F. Fox, W . S . Robinson, R. Hasellcorn, and S. B. Weiss,
J . biol. Chemistry 239, 186 (1964). - Reaction mixture (0.3 ml,
pH 7.5): 0.1 M Tris, 0.4 mM [3H]-CTP, [3H]-UTP, or[XH]-ATP.
specific activity 5.5 to 10 mCi/mmole, 20 ! r g of poly-A, poly-C,
or poly-U, 6 enzyme units of polymerase from Micrococcus lysodeikticiis (Miles Chemical Co.), and optimal concentrations of
MnC12.
Synthesis of a Catena Compound by the
Semistatistical Principle
By A . Liittringhaus and G. Isele [*I
Cyclization of the dinitrile ( I ) 111 by Ziegler’s method [21
affords the isomers (2) and (3) as viscous oils that are
separable chromatographically on silica gel but give identical
IR and N M R spectra. Since these products also give identical
mass spectra (the same molecular ion and similar fragments),
they are stereomers or topological isomers [31, differing only
in that the macrocycles of (2) are intraannularly, and of (3)
extraannularly, combined by the N atom.
The total yield from the cyclization amounted to 57 %. Of
this, 5-8 % consisted of (2) and 92-95 % of (3). Proof that
only (2) is a pre-catena compound was provided by cleavage
of the nitrogen-phenyl bond by way of the o-quinone according to the pattern established by SchiZlr41. Compound
(3) was cleaved into compounds (4) and (5), but compound
(2) was converted into the catena-compound (6). The
product (6) was shown to be homogeneous by thin-layer
chromatography; its I R spectrum contains the expected CO
frequencies at 1780 @henolic acetyl groups), 1720 (keto
group), and 1650 cm-1 (N-acetyl).
The mass spectrum of (6) is completely analogous to that
of the catena-compound (7) prepared by SchiNr41 by “planned” synthesis. Compound (7) is a homologue of (6),
having a heterocyclic ring smaller by 2 x 5 CH2 groups; its
mass spectrum was analysed by Vetter and Schill[51. The
mass spectrum of (6) shows the molecular ion at m,/e = 1161;
then follow, with increasing intensity, fragments at i ~ / =
e
1119, 1077, and 1035 (base peak) corresponding to stepwise
removal of three molecules of ketene from the three 0acetyl groups; in the region mie = 600 to 990 the mass
spectrum is empty; below m:e = 600, the fragments of the
separated rings appear, as is to be expected for a catenane of
this structural typecsl. Thus the catena structure of (6) is
proved too by the mass-spectrometric evidence.
Angew. Chem. internat. Edit.1 VoI. 6 (1967)
1 No. I 1
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