250 CHAS. E. SANDO 
Table 6. Data Leading to the Selection of C7H5O4 as the Formula of Endothine Red 
Found 
Required for 
C7H0O4 
C9H705 
C H 
C H 
C H 
C H 
55-00 3.53 
54.88 3.29 
55.27 3.61 
54-77 3-6i 
54-62 3.58 
54.40 3.58 
54.87 3.51 
mean 
54-73 3-55 
- 
Acetyl Derivative 
C7H404(C2H30) = 
TT r\ f TT r~\\ 
C9H605(C2H30) = 
tt /~\ //^ TT /^\ 
Ci4H808(C2H30)3 = 
rl 
55-27 C 3-61 H 
55.67 ^ 3.02 rt 
1-1- . ^ n r^C U 
55.40 C 3.96 H 
55-01 4.03 
C7H304(C2H30)2 = 
TT r\ / tt r\\ 
C9H505(C2H30)2 = 
TT /~\ //~* TT /^\ 
Ci4H708(C2H30)4 = 
54-99 4-03 
55.67 C 3-82 H 
55.89 c 3.97 H 
55-56 C 4.03 H 
55-60 3.93 
C7H204(C2H30)3 = 
C9H405(C2H30)3 = 
Ci4H608(C2H30)5 = 
mean 
55.89 C 3-97 H 
56.05 C 4.08 H 
5S.68 C 4.09 H 
55.20 4.00 
Yield of Regener- 
ated Pigment 
C7H404(C2H30) = 
C9H605(C2H30) = 
d4rl8U8(C2rl3Uj3 = 
64.82 
78.97 
82.27 
64.50 
C7H304(C2H30)2 = 
C9H505(C2H30)2 = 
L-i4hl7U8(L.2l:i3L);4 = 
64.66 
64.55 
! 69.89 
64.62 
mean 
C7H204(C2H30)3 = 
C9H405(C2H30)3 = 
tt r\ f tt r\\ 
Ci4H608(C2H30)5 = 
64.66 
54-48 
60.74 
59,37 
Acetic acid from 
Acetyl Derivative 
C7H404(C2H30) = 
C9H605(C2H30) = 
Ci4H808(C2H30)3 = 
46.4s 
30.78 
25.32 
41.81 
47-34 
C7H304(C2H30)2 = 
C9H505(C2H30)2 = 
Ci4H708(C2H30)4 = 
46.80 
50.64 
43.01 
50.53 
45.68 
C7H204(C2H30)3 = 
C9H405(C2H30)3 = 
Ci4H608(C2H30)5 = 
mean 
64.52 
56.08 
58.03 
46.57 
Regenerated Pigment 
C H 
C H 
TT 
SzL 80 ^ 68 
54.88 3.29 
55-27 3-61 
SS 77 ^.61 
Molecular weight of 
Acetyl Compound 
C7H404(C2H30) = 
C9H605(C2H30) = 
1 70 I C^) 
195.06 
237.07 
241.9 
C7H304(C2H30)2 - 
C9H505(C2H30)2 = 
Li4rl7U8(,C2rl3Uj4 = 
216.3 
237.07 
279.09 
A'-! C T C 
C7H204(C2H30)3 = 
C9H405(C2H30)3 = 
Ci4H608(C2H30)5 = 
mean 
279.09 
321.10 
517-17 
220.1 
Na from Sodium 
C7H404Na = 13.16 
CgHeOsNa = 10.59 
Ci4H908Na2 = 13.13 
Derivative 
C7H304Na2 = 23.38 
C9H505Na2 = 19.27 
Ci4H808Na3 = 18.52 
T n c c 
C7H304Na2,2H20 = 
IQ S7 
19.77 
mean 
C7H204Na3 = 31-54 
C9H405Na3 = 26.47 
Ci4H708Na4 = 23.32 
19.56 
Ba from Barium 
C7H304Ba = 47.63 
CgHsOsBa = 41.57 
Ci/.OsBaa = 47-54 
Derivative 
C7H304Ba, 2H2O = 
42.06 
42.35 
41.92 
mean 
41.98 
