Illti
ALFRED BURGER,E. L. WILSON,C‘. 0.BRINDLEY .WD FREDERICK BERNHEIM
[ C O N T R I B U T I O N FROM THE C O B B C H E M I C A L LABORATORY, L X I V E R S I T Y OF V I R G I N I A , AXD T H E COLOGY AYD P H \ W O L O G Y , DrJKP, ~7\;IVERSIT1’ h f E D l C A L S C H O O L ]
V O l . OT
DEPARTMENT O F PHARMA-
Synthesis and Antitubercular Studies of Halogenated Phenyl Ethers BY A L F R E D
B U R G E R , ELIZ \BETH
1.. W I L S O N , ’
c. 0.BRINDLEYAND FREDERICK BERNHEIM
The tuberculostatic properties of 2,-l,ti-triiodo- iodine does not appear superior to other halogens phenol were first described by Carrasco,2 who in the tuberculostatic activity of this series. introduced bismuth salts of this compound under The basic aromatic ethers are listed in Table I. the name of Neoform into a short-lived thera- Although only a few non-halogenated dialkylpeutic practice. More recently, Saz, Johnston, aminoalkyl phenyl ethers have been tested it Burger and Bernheini3 observed that triiodo- appears that such compounds lack antitubercular phenol itself is bacteriostatic, and some of its di- properties. Therefore, simpler non-basic phenyl ethylaminoalkyl ethers are bactericidal in their alkyl ethers were not tested. However, several action on human and bovine tubercle bacilli in polyhalogenophenols and -anisoles exhibited an vitro. Oxygen uptake by the bacilli was de- in vitro inhibition up to 83%. In vivo inhibition creased, growth in vitro inhibited by several of was negligible, perhaps owing to the low solubility the drugs tested, and the formation of tubercles of these derivatives. Lengthening the alkyl in the omentum of infected guinea pigs was re- chain from one carbon atom in the bacteriostatic duced. Based on this latter observation, an in trihalogerio anisoles to twelve carbon atoms, in vivo screening test was worked out which promised n-dodecoxy-2,4,6-triiodobenzene and its 3-methyl to accelerate considerably the initial evaluation of homolog, abolished this activity, probably because new antitubercular drugs as compared with the of the insolubility of these ethers in polar solvents. traditional laborious testing methods, and to re- We had hoped that their high solubility in hydroduce the quantity of the drug required in those carbons would increase their chance of penetrating the lipid capsule of the acid-fast bacilli, and tests. In order to explore the significance of the di- enable the “toxic” triiodophenoxy group to exert ethylamino group in the ether chain of the active a more pronounced action on the organisrns. cthers, l-(2,4,6-triiodophenoxy)-2-(4-morpholino~- In the preparation of the starting materials, ethane was tested, and, unexpectedly, found to be various commercially available phenols were devoid of tuberculostatic activity. This led us iodinated in an arnriioniacal medium. The anito synthesize a number of dialkylaminoalkyl soles were prepared from the corresponding soethers of iodinated phenols with variations in the dium phenolates with dimethyl sulfate in aqueous structure of the ether chain (1) 111 general, solution while the dialkylaminoalkyl ethers were synthesized from the sodium phenolates and dialkylaminoalkyl halides in methanol solution by the Williamson reaction. The dialkylaminoalkyl halides were prepared from commercial dialkylchemotherapeutic activity was not restricted to amino alcohols with thionyl chloride. compounds containing aliphatic amino groups ; The 1:turyl ethers listed in Table I1 were obseveral ethers containing the 2-methylpiperidino- tained from sodium triiodophenolate, and cresopropyl radical were highly active. Activity, but late, respectively, and lauryl iodide in methanol also toxicity in guinea pigs, was usually greater solution. in dialkylaminopropyl than in the corresponding 2,4,5 - Trichlorophenoxy - diethylaminomethdialkylamino ethyl ethers, while shortening of ane was synthesized by condensation, of diethylthe ethylene group, in a trihalogenophenoxy di- aminomethyl chloride hydrochloride4 with soethylaminomethane derivative caused complete dium 2,4,5-trichloropheriolatein the presence of loss of antitubercular action. Replacement of sodium methoxide. the dibutylamino group in an active ether by the Acknowledgment.-The authors are deeply secondary monobutylamino group also abolished grateful to Dr. Charles C. Haskell of Richmond, activity. Virginia, for a generous grant which made these Replacement of nuclear iodine by other halo- studies possible, and to the Duke University Regens did not lead to a definite pattern correlating search Council for funds used in this research. chemical structure to antitubercular activity. The technical assistance of Miss Joan Elliott and Nuclear bromine had a slightly dystherapeutic Mr. Edward Stanley-Brown in the preparation of d e c t while several of the polychloro derivatives some of t h e starting materials has been very helprivaled analogous iodinated compounds. As the ful. only tangible result of these variations, nuclear Experimental ( 1 ) Charles C. Haskell Fellow, Gniversity of Virxinia. 1943-184.1. (2) Carrascu, E d : . c h i n i - f o r t ; , . 47, I l W ( 1 9 0 8 ) . i ‘ k c v t Z P J Z ~TU, V., J , 1735 (1908). (3) Saz, Johnston, Burger and Brrnhrim, A m R m :‘14brrc., 48, 40 11943).
Iodination of Phenols.-In general, 100 g. of the phenol was dissolved in a mixture of 800 cc. of 20y0 ammonium ( 4 ) Pr4vost a n d d e Mauny. l - ’ o ~ n P l r e d . , 216, 771 (1913); C. A , ,
38, - l i C , X S (1944;.
AUg., 1945
SYNTHESIS AND
ANTITUBERCULAR S T U D I E S O F
HALOGENATED PHENYL ETHERS
1417
TABLE I 8
'pq%
inhibited i n vitro
growth of 6
6
-Phenoxy 2,4,6-Triiodo
n
2,4,6-Triiodo
2
2.4.F,-Triiodo
2
2 .?,K-'L'riiodo 2,6-Diiodo-4-bromo 2,6:Diiodo-4-chloro 2.4-Diiodo-6-chloro 2,6-Diiodo-4-ahloro 2,4-Diiodo-6-chloro 2,6-Diiodo-4-phenyl 2 ,6-Diiodo-4-metbyl 2.4- Diiodo-6-methyl 2,4,6-Triiodo-3-methyl
3
2
2
2 2 3 3
2 2
2 2
NR: NMen.HC1
182-194 d CleHzdIjNO.HC1 N(TRBU)P HC1 130-131 Morpholiiio" Ci?HirIaNO? 210-242d ,HCla CizHirIaNOr HCI 190-192d NEtt.HC1 CisHlsInN0,HCI NEtyHCl CizH~sBklzNO~HCI 174-177 d 182d NEt?.HCl CizHieC1lzNO.HCI Ci~HioCIIzNO~HCI 155-156 NEt?.HCI NEtvHCl CirHiaClI~NO~HCI 2 1 4 d 188d N C ~ H ~ ~ . HCiaHzoCll~NO~HCl CI~ 198-199d NEtyHC1 CiaHziIzNO~HCl 166.5 NEtvHCl CisHioIzNO~HCI 151-152 NEti.PCI CnHisIzNO,HCI 173-174 NEtvHCl CiaHirIsNO.HC1
2,4,6-Triiodo-3-methyl 2 N(n-Bu)z. HCI 2,4 ,6-Triiodo-3.52 NEtvHCI dimethyl 2 NEtyHCI 2-1 odo-4-phenyl-6hromo 2.n-l)iiodo-4-phenylaeo 2 N Ht,.HCl 2 .-1,e-Tribromo 2 NMer.HCI 2,4,6-'Yribromu 2 NEtrHCI 2.4.6-Trichloro
2
2,4,6-Trichloro 2.4 ,B-Trichloro 2,4,5-Trichloro 2,4,5-Trichloro 2,4,5-Trichloro
2,4,5-Trichloro 2,4,5-T+ichloro 2,4-Dichloro Pentachloro
Formula CinHizIaNO.HC1
M. p., OC. (d denotes decomp.) 226d
Analyses, % Calcd. Found C 20.72 21.01 H 2.26 2.53 CI- 5.34 5.71 N N CIClC1ClCIC1ClC1C1C H C H
2.39 2.67 2.25 2.41 5 . 7 1 0.37 6 . 3 3 6.36 6.86 6.86 6.86 G.73 6.70 6 . 6 8 6.38 6.30 6.36 6.58 7.16 7 . 0 6 7.16 7.23 25.24 25.20 2 . 6 1 3.04 30.10 29.88 4.02 4.05 65.49 65.40
CirHzaIaNO~HCI
190-193 d
CirHzoIaNO.HCI
209d
CisHYiBrINO.HC I
190-191 d
C1- 6.93
6.82
CiaHzi 1rNnO.HCI CioHinBrrNO.HC1 CizHieBraNO.HC1
188-190d 194 149
C1- 6 . 0 5 C1- 8.09 C1- 7.60
6.40 8.33 7.60
NMez
CioHizClrNO
Picratec NEtrHCI
CiaHisClaNiOa CizHiaCliNO.HCI
X
B. D. 131133 i4 mm.) N 11.26 12.04 192-193 C1- 10.62 10.73 160-162
156-157 N C O H I Z . H CCi6HzaClaNO~HCI ~~ d NEtrHCl C I I H I ~ C ~ ~ N O ~ H 157-159 CI 210-21 1 NMerHC1 CioHirClrNO.HC1 183 NEtz.HC1 CizHisClaNO~HCl
c1c1C1C1-
N(n-Bu):. HC1 NEtrHC1 N(n-Bu)r
124
c1-
179
C1- 10.13 10.35
CisHziClrNO.HC1 CiiHi~ClrNO.BC1 CirHz#ClrNO
Picrate" CxaHzoCIaN~Oa 3 N C ~ H ~ ~ . Ci6HzoClsNO~HCI HC~~ 2 NH(n-Bu). CiiHisCIaNO.HC1 HC1 2 N(+Bu)r CisHzrClnNO.HC1 HCl 3 N C ~ H ~ ~CiIHisClsNO.HC1 H C ~ ~
Unsubstituted
2
NEtr.HC1
CizHioN0,HCI
4-&Butyl 4-&Amyl 3-Methyl
2 . NEtnHCI 2 NEtrHC1 2 N(n-Bu)i
CisHz7NO.HCI CirHisNO.HCI CirHzoNO
3,5-Dimethyl
2
CirHzaNO.HC1
NEtyHCl
9.80 9.02 11.09 11.10 11.59 11.70 10.62 10.44
9.11
9.26
b
B.p. 180-
190 (2 mm.) 119-120 N 9.40 9.46 229-230 Cl- 9.50 9.87 122 X 42.58 43.55 295-297 224d
137.5
C H C H
54.18 53.45 7.39 8.87 40.76 40.60 4.33 4.36
C H ClCI-
62.73 62.77 8.71 8.57 12.86 12.38 11.8'2 11.84
153-160 128-131 B. p. 147150 (1 mm.) 132 CI- 13.75 13.16
tubercle bacillus Y%
n
y
3
90
5
00
3 3 3
96 95 86
3 3 5 5 3
62 88 95.4 97.7
n mg./kg. reduced omental wt. per 100 g. guinea pig t o x g. (control, Y K.) n
x
100 0.73
Av. w t . loss of animal
Y
in g.
0.83
811
51)
.IW
,75
30
,117
.08
70
50 50 50 50 50 50 50
.58
.69 ,915 .93 .69 .81 .81 1.1
124 149 39 76 113 51
.87 .97 .58 .71 .81 1.1
20
69
TOO
insol.
3 3
76.6 56.2
5
95.5
5 5
82.6
52.2
5 3 2 5 5 3
00 92.1 61.5 67.2 72.1 97
50 1 . 1 1.1 100 0 . 6 1 0.75 100 ,232 .R1 100 .52 .75 50 .78 .91
60
54 39
50
.79
.98
50
50
.83
.93
64
50 60
.77
..
.9! .63
50
.82
.98
50 50
.82 .60
.83 .69
50 50
.68
.09 .71
50
$83
.93
50 50
.93 -95
.72 .62
50
.73
.83
5 pig9 died 42
50 50 50
.88 .94 1.18
.93 .83 .95
67 52 84
50 0.63
68
52
.52
60
All animals died 65 40 55
100 Very toxio 38 8W
Prepared by Dr. K. C. Bass, Jr. * The free oily base was not analyzed. For physiological experimentation, it was dissolved in one mole of dilute hydrochloric acid. e The picrate was prepared in ethanol solution, and recrystallized from the same solvent. NC6.fll signifies the 2methylpiperidino group. @
hydroxide and 200 to 800 cc. of methanol with mechanical stirring at room temperature, and the calculated amount of an iodine solution, containing one part of iodine and two parts of potassium iodide in four parts of water, was added a t such a rate that the brown color of iodine never persisted for any length of time. The iodine usually was absorbed rapidly in the beginning, and more slowly to-
ward the end of the substitution. An occasional precipitate of nitrogen iodide which appeared in the reaction mixture went back into solution as absorption progressed. The reaction product precipitated directly from the mixture, or, in a few cases, was obtained on dilution with water. The iodinated phenols were recrystallized from methanol, methanol-water, or acetic acid. The yield of
n ma.% inhibited rn rilro growth of tubercle
Same
Analyses, % Cctlcrl r'niind
',.l,ti-TriiodoanisoIc
?' ,I
2 5 5 3
Halogell 7 3 . 3 3 72.85
2,4,6-Triiodo-n-dorlecosybenzene 2,4,6-Triiodo-3-mettiyl-ndodecoxybenzene" 2,4,0-Triiodo-3,5-dimcthyl phenol 2,4,6-Triiodo-3-niethylphenol 2,4-Diiodo-~-t-arnylpheiiol 2-Bromo-4-phenyl-6-iodophenol 3,1-Diiodo-4-t-butylphenol Recrystallized froin acetone
l>aclllus
C, 33 77 €3, 4 22
33 4 c , 34 88 34 IT, 4 17 4 T 76 lfi 75
the crude reaction product was above 90'); but ci-20"c of the material was usually lost during the purification. The calculated amount of iodine was, in our experiments, the maximum number of moles of iodine needed to substitute all the available positions ortho and paru to the phenolic hydroxyl group. We found that this amount of iodine was absorbed regardless of the nature, or the relative position of other substituents in the aromatic nucleus. The phenols serving as starting materials in these iodinations were obtained from the Eastman Kodak Co. Preparation of Dialkylaminoalkyl Chlorides.-One mole of thionyl chloride, dissolved in twice its volume of dry benzene, or in c h l o r ~ f o r t nwas , ~ added dropwise, and with stirring, a t -5" to a solution of one mole of the freshly digtilled dialkylamino alkanol in twice its volume of one of the solvents mentioned above. The addition required one to two hours. The mixture was refluxed with stirring on a steam-bath for three to five hours and allowed t o cool. The crystalline dialkylaminoalkyl chloride hydrochloride was filtered, washed with acetone, and recrystallized from ethanol-ether. When chloroform was used as a solvent, it had to be removed under reduced pressure to permit crystallization of the crude hydrochloride. The yields were 80-90Yc. None of the pure salts used hy us was appreciably hygroscopic. I n order to obtain 6-di-n-butylaminoethyl chloride hydrochloride, the solvent (either benzene or chloroform) had to he removed, and the crystalline salt was recrystallized from benzene-ether. It was extremely soluble in acetone, and not hygroscopic when pure. The crude hygroscopic salt did not always crystallize readily but had t o stand at 4' for several days in a number of runs. ,8-n-Butylaminoethyl chloride hydrochloride was prepared in an analogous manner. Dimethyl- and diethylaminoethanol and morpholinoethanol were furnished bv Carbide and Carbon Chemicals ( 5 ) The preferential use of this solvent was recommended to us by hlr. H. A , Shonle, T.il!y Research Laboratories, Indianapolis, I n d .
56 26 62 44 64
%
?'
25 85. 5 70. 0 75.4
3 95.4 5 97.8 40 83
mg./kg./day reduced nmental w t . from y g (control) to z g
iz
if
1
Y
Av. wt. loss of animal, g Remarks
Wl
0 A0
0 63
M
60 50
(il
.ti3
.63
.75
00 00
100
.81
.R?
60
100
.81
.&3
40 3 deaths
,
Too toxic 5
6
75
1.1
1.1
Too insol.
5 54.0 .we purchased from Eastman Kodak Co. Preparation of Dialkylaminoalkyl Aryl Ethers.-In most of these experiments, 0.1 mole of the phenol was dissolved in a solution of 0.2 mole of sodium in methanole (about 10 cc. per g. of phenol) at 30-50'. Twelve hundredths of a mole of the dialkylaminoalkyl chloride hydrochloride was added in one batch, and the mixture refluxed for five to twelve hours. Sodium chloride precipitated immediately, and bumping could be reduced b y frequent shaking or stirring. Since the dialkylaminoalkyl chlorides, especially the dialkylarninoethyl chlorides, have a tendency to polymerize, their reaction with the sodium phenolates was accelerated by addition of 0.1 mole of sodium iodide to the reaction mixtures. However, the yields of the basic ethers were not improved appreciably by this procedure. The precipitated sodium chloride was filtered, the solution evaporated under reduced pressure, the gummy semi-solid residue extracted with ether and water, and the ether solution washed repeatedly with 25Yc sodium hydroxide solution and with water. Insoluble precipitates of recovered sodium polyhalogenophenolates frequently appeared at the interphase. The ether solution was dried over sodium sulfate, the solvent removed, and the oily base converted to the hydrochloride in acetone-ether solution. I n a few cases, the hydrochlorides did not crystallize; the basic ethers were distilled at 1-3 mm., and the oily distillates used directly, or in solution in one equivalent of dilute hydrochloric acid, for the bacteriostatic tests. No attempt was made t o distil (6) Methanol was used for all iodinated phenols while ethanol gave equally good, or better, yields of ethers containing halogens other than iodine.
.ha.,
1945
ethers containing iodine. The hydrochlorides were recrystallized from methanol, ethanol, methanol-ether, acetone, or ethyl acetate-ether. The yields in the Williamson reactions averaged 2645%. Low yields, sometimes below 5%, were obtained in several preparations involving dimethylaminoethyl chloride. Dialkylaminopropyl chlorides usually rendered the corresponding aryl ethers in yields of 50-90%. However, the optimum conditions have not been determined in all cases. 1-(2,4,5-Trichlorophenoxy)-2-n-butylaminoethane was prepared from n-butylaminoethyl chloride in an analogous manner. The yield was 18%. 2,4,5-Trichlorophenory Diethylaminomethane.-Dic thylaminomethyl chloride hydrochloride was obtained in Slyo yield by the direction of Prkvost and de Mauny' and condensed with sodium 2,4,5-trichlorophenolate according to the procedure outlined above. The yield was 50'
' /o.
Chemical Analysis.-Most of the hydrochlorides listed in Table I were titrated in water or dilute alcohol solution with 0.05 N potassium hydroxide solution t o a phenolphthalein end-point. For several hydrochlorides, and water-insoluble deriva-
Isolation of Rutin from Hydrangea Paniculata, Var. Grandi,Rora Sieb. BY
JAMES F.
1410
NOTES
COUCH
AND JOSEPH
NAGHSKI
Rutin, 3,5,7,3',4'-pentahydroxyflavone-3-rutinoside, has recently assumed some prominence in the treatment of increased capillary fragility associated with hypertension'J and is promising as a remedy for certain other diseases resulting from capillary breakdown. Rutin has been found in thirty-three species of plants and is, thus, one of the most widely distributed of the glucosides. This paper reports the isolation and identification of rutin in the flowers of a common garden species of Hydrangea. Previous chemical examinations of the roots of white-flowered species of Hydrangea have been r e p ~ r t e d . ~ *Hashimoto ~i~ and Kawanas extracted the dried flowers of H. paniculatu with benzene and obtained a phenolic substance, CaHsOa, but they do not mention rutin. The presence of rutin in relatively large quantities in the flowers has not previously been reported. Experimental.-Fresh blossoms (67.5 g., moisture, 83.6%) were digested with alcohol (300 ml.) for several hours. The solvent was removed from the filtered extract. The residue was freed from fats and resins with benzene (1) J. Q. Griffith, J. F. Couch and M. A. Lindauer, Proc. SOC.E x p . Mcd. B i d . , 66, 228-229 (1944). (2) J. F. Couch and C. F. Krewson, United States Department of Agriculture, Mimeograph Circular AIC-52, July, 1944. (3) C. S. Bondwant, Am. J . Pharm., 69, 122-124 (1887). (4) A. G. Leubert, ibid., TO, 550-552 (1898). (5) H. J. Ivl. Schroeter, ibid., 61, 117-118 (1889). (6) A. Hashimoto and T.Kawana. J Pharm Soc J a p a n , 66, 183186 (1935); C. A . , 19, 5112 (1985).
tives, the total halogen content was determined by the method of Schwenk, Papa and Ginsberg,' using samples of 30-80 mg. and correspondingly small amounts of the required reagents. The silver nitrate and potassium thiocyanate solutions were 0.05 N. Reliable results were obtained on this semimicro scale with most of the compounds; those derivatives analyzed for carbon, hydrogen or nitrogen did not give consistent halogen values by reduction with Raney nickel alloy.
summary A number of alkyl and dialkylaminoalkyl ethers of phenol and halogenated phenols with various substituents has been described. It has been found that nuclear iodine is not a prerequisite for the antitubercular action of such compounds. (7) Schwenk, Papa and Ginsberg, I n d . E r g . Chem., Anal. E d . , 16, 576 (1943).
CHARLOTTESVILLE, VA. DURHAM, N. C.
RECEIVED APRIL 25, 1945
and the insoluble matters were extracted with boiling water. On coolitg and standing, 0.4 g. of rutin crystallized, m. p. 183-185 ' raised by recrystallization from boiling water A further crop, 0.05 g., was obtained by to 190-162'. re-extracting the insoluble matters with boiling water; yield, 0.45 g. or 4.06% of the moisture-free.plant. Anal.? Calcd. for C2,HloOl~:C, 53.10;H, 4.95. Found: C, 53.34; H, 5.09. The substance gave the usual tests for the identification of rutin. These data were confirmed on a larger sample (1.6kg.) of fresh flowers. (7) C and H determinations by C. L. Ogg.
AGRICULTURAL RESEARCH ADMINISTRATION BUREAUOF AGRICULTURAL AND INDUSTRIAL CHEMISTRY UNITED STATES DEPARTMENT OF AGRICULTURE EASTERNREGIONAL RESEARCH LABORATORY PHILADELPHIA, PA. RECEIVEDMARCH26, 1945
sym-Tetraphenylethane from DDT and Related Compounds' BY ELMERE. FLECK,ROBERTK. PRESTONAND H. L. HALLER
During an investigation of the effect of various solvents on the dehydrochlorination of l-trichloro-2,2-bis-(p-chlorophenyl)-ethane (known as DDT),2it was noted that a n abnormal reaction took place in the presence of anhydrous aluminum chloride and benzene. When one mole of anhydrous aluminum chloride was used with a large (1) Some of the work reported was done under a transfer of funds, recommended by the Committee on Medical Research, from the office of Scientific Research and Development t o the Bureau of Entomology and Plant Quarantine .4rticle not copyrighted (2) Fleck and Haller, THIS JOURNAL, 66,2095 (1044).
