181.
Unit Cell Dimensions and X-Ray Powder Data of Prednisolone Acetate R. A. PASTERNAK, Stanford Research Institute, Menlo Park, Calif.
T
serred-(OkO) absent for k odd-are indicative for the space group P21. The unit cell dimensions are: a = 9.07.
note reports the results of an x-ray crystallographic study, both powder and single crystal, of prednisolone acetate. HIS
0
11
CHzOCC Hd
I
c=o cH~I
, , l , , \OH
.___.._
OH
I
CHai
;"'\/0
-
;
/v\/
a steroid of potential importance in the treatment of arthritis. The steroid (melting point 229' to 234' C.) was furnished by the Schering Corp. Single crystals of prednisolone acetate were obtained by s l o evaporation ~ of its chloroform solution. They showed monoclinic prismatic habit. Rotation, OkZ and h01 Keisenberg photographs were taken for two crystal specimens. The only systematic absences ob-
~
Table I. Powder Data for Prednisolone Acetate, Co Kci Radiation d, A. Line Intensity4 8.81 1 m 2 vvw !.32 l.46 vvw 3 S i. 11 4 m 6.92 5 m 6.18 6 5.45 vs 5.34 m 5 10 m 9 4.89 mw 10 4.29 m 11 4.13 mw 12 13 ms 3.9s 14 vu. 3.85 15 ni 3.56 16 W 3.3; 17 m 3.21 1s mw 3.11
~~
~~~
a
19
w
2.93
20 21
m m
2.Ti 2.66
w = weak, m = medium, s
=
v = very.
strong,
b = 13.94, c = 8.58 A. =t 0.37,. fl = 103.4'. The experimental density determined by flotation is 1.27 grams per cc. The molecular weight calculated from these data and assuming two molecules per unit cell is 404. It compares well with the theoretical value of 402.5. For identification purposes powder photographs of prednisolone acetate were also taken. I n Table I the relative intensities and spacings of 21 lines are reported. The first 10 entries include all observable lines in this range of d values, the other entries only the stronger reflections. ACKNOWLEDGMENT
The author is grateful to the Schering Corp., Bloomfield, X. J., under whose support this study was carried out, for permission to publish the data, and t o Dean Graham for growing the single crystals. CRYSTSLLOGRAPHIC data for publication in this sertion should be sent to W, C. hIcCrone, 501 East 32nd St., Chicago 16, Ill.
~~
Analysis of Detergent-Slurry Components CS-76
V. A. CIRILLO, The Atlantic Refining Co., Philadelphia, Pa.
Calculation:
No.!
-1
Component Name 1 Formula
1
Benzene
2
Water
~ c c u -1 racy
Range ~
%
~
%
1
x or u
Solvenfs:
B.1.
Ah or
length
Points
AU
mm
-1
H?O
I
'
0.56 0.04 0.06611 0.100 _ _ _ I
9.88
dodecyl ~
~
benzene sulfonate
, 1
I
I
Insfrument: Beckman IR-4, NaCl prism Sample Phase: Slurry or emulsion Cell Windows: AgCl Absorbance Measuremenf:
Acetone and dioxane
Relative Abrorboncesa-Analyfical Matrix: Component/X
CsHs
1
Inverse matrix--
1 2 33 4
14.57 26.8 0 0 0
6.07 0
13.6 0.12 1.80
9.63 1.07 1.82 33.0 5.11
9.88 0.03 1.90 3.60 4.59
Materiol Purity: Reference compounds 99 +% pure Comments: ~ Slurry is heated slightly until a solution results. Two 1-mi. aliquots are weighed in 25-mi. volumetric flasks containing dioxane and acetone, respectively. The benzene bond at 14.57 microns differs from its usual position 14.86 microns in less polor solvents. It i s necessary to scan only the following regions: Benzene. 15.0 to 14.0 microns, acetone solvent Methanol detergent. 10.4 to 9.0 microns, acetone solvent Woter. 7.1 to 5.8 microns, acetone solvent a Relative absorbances are given as the slope of the Beer's law concentration curves used exmessed in terms of absorbance Der 100% of constituent. I "
Base line:
Benzene
Point:
All others
VOL. 31, NO. 5, MAY 1959
959
