This work has been digitalized and published in 2013 by Verlag Zeitschrift für Naturforschung in cooperation with the Max Planck Society for the Advancement of Science under a Creative Commons Attribution4.0 International License.

Dieses Werk wurde im Jahr 2013 vom Verlag Zeitschrift für Naturforschungin Zusammenarbeit mit der Max-Planck-Gesellschaft zur Förderung derWissenschaften e.V. digitalisiert und unter folgender Lizenz veröffentlicht:Creative Commons Namensnennung 4.0 Lizenz.

Preparation of N,N,N',N'-Bis(ethylene)-phosphorodiamidates of Steroids, Diacetone-D-glucose, and a-Tocopherol

G . S O S N O V S K Y a n d M . K O N I E C Z N Y

Department of Chemistry, University of Wisconsin-Milwaukee, USA

(Z. Naturforsch. 31b, 1379-1381 [1976J; received June 30, 1976)

Diacetone-D-glucose, Phosphoroclichloridates, a-Tocopherol, Steroids, N,N,N',N/-Bis(ethylene)-phosphorodiamidates

The phosphorodichloridates (1) of cholesterol, /9-sitosterol, testosterone, cliacetone-D-glucose, and tocopherol were prepared from phosphorus oxychloride in the presence of triethylamine. Tocopheryl phosphorodichloridate was too unstable to be isolated. Reaction of 1 with ethyleneimine in the presence of triethylamine gave the corresponding N,N,N',N'-bis(ethylene)-phosphorodiamidates (2).

It has been reported1-5 that numerous derivatives of pentavalent phosphorus containing the aziridine moiety exhibit biological activity against various tumor cells. In the course of our studies of the preparation of the N,N,N',N'-bis(ethylene)-phos-phorodiamidates (2) of cholesterol, ^-sitosterol, testosterone, diacetone-D-glucose, and tocopherol for biological testing, it was necessary to prepare the phosphorodichloridate derivatives (1).

Et N P0C13 + ROH — — — • R0P(0)C12

Et 2 0 or C6H6 j

ROH = cholesterol, ^-sitosterol, testosterone, diacetone-D-glucose, tocopherol

Et3N 1 + 2 H N C ] — — • R0P(0)(NC])2

While attempting to prepare cholesteryl phos-phorodichloridate, difficulties were encountered in reproducing the procedures of CREMLYN , DEWHURST,

and WAKEFORD6'7. Cholesteryl phosphorodichlori-date was reported to have been prepared by the reaction of phosphorus oxychloride with cholesterol in ether in the presence of triethylamine. Under the conditions reported by the authors, dichloridate (1) (R = cholesteryl) apparently was completely insolu-ble in ether and could be collected together with

Requests for reprints should be sent to Prof. Dr. G. SOSNOVSKY, T h e Univers i ty of Wisconsin-Milwaukee, Department of Chemistry, Milwaukee, Wisconsin 5 3 2 0 1 , U S A .

triethylamine hydrochloride by filtration. Washing of this mixture of solids with water removed the triethylamine hydrochloride and gave pure 1 (R = cholesteryl) in high yield. However, we found that the cholesteryl phosphorodichloridate is in fact completely soluble in ether under the reported conditions, and therefore cannot be collected by filtration as suggested. Only by decreasing the amount of ether by approximately a factor of 3 could 1 (R = cholesteryl) be isolated as de-scribed6-7, though in a reduced yield (45%) (see Experimental, Method A). However, a higher yield of cholesteryl phosphorodichloridate could be obtained in the reaction mixture was filtered to remove the triethylamine hydrochloride, and the filtrate concentrated to approximately 1/5 of its original volume. Thus Ave obtained cholesteryl phosphorodichloridate in an 89% yield (see Experi-mental, Method B).

The /S-sitosteryl phosphorodichloridate was pre-pared in an analogous manner. Due to the poor solubility of testosterone in ether, benzene was the solvent of choice in preparation of testosteryl phos-phorodichloridate. Benzene was also used to prepare diacetone-D-glucosyl phosphorodichloridate, since ether afforded a product of inferior quality. The tocopheryl phosphorodichloridate was unstable and could not be isolated. The colorless ethereal filtrate containing 1 (R = tocopheryl) rapidly darkened to a greenish oil on removal of the solvent. The results of these experiments are shown in Table I.

1380 G. Sosnovsky-M. Konieczny • Preparation of N,N,N',N'-Bis(ethylene)-phosphorodiamidates

Table I. Preparation of phosphorodichloridates (1).

P O C I ° + R 0 H EtsO or CeHs " K ™ 1 *

ROH Yield m.p. with Solvent Mol. Wt. 1 [ % ] dec. [°C] (found)

Elemental Analysis

79 124-126a Ether

90 114-116 Ether

C27H45CI2O2P calcd C 64.40 H 9.01 503.539 found C 64.19 H 8.79

(512)

C29H49CI2O2P calcd C 65.52 H 9.29 531.593 found C 65.44 H 9.53

(527)

Testosterone

H 3 C X ° ~ T H 2 H3C O - C H H

85 62-64

T ^ O CH3

H CH]

Diacetone -D-glucose 90 71

C19H27CI2O3P calcd C 56.31 H 6.71 405.305 found C 56.24 H 7.00

Benzene (426)

C12H19CI2O7P calcd C 38.22 H 5.08 377.161 found C 38.09 H 5.32

Benzene (386)

CH3 CH3 CH-J CH-, Lir l o r 3 I 1 I

JOC j (CH2'3CH (CH2>3 CH (CH2>3CHCH3

CH3 ot-Tocopherol

not isolated1* — Ether

a Lit. 6>7; m.p. 123 °C; b unstable.

Phosphorodichloridates (1) were reacted with ethyleneimine in the presence of triethylamine to prepare the N,N,N',N'-bis(ethylene)-phosphorodi-amidates (2) in high yield. Almost identical yields of 2 were obtained with and without isolation of the intermediate dichloridates (1). The latter procedure was particularly advantageous in the case of toco-pheryl phosphorodichloridate, which could not be isolated, and the somewhat sensitive dichloridates (1) of testosterone and diacetone-D-glucose. Thus the analytically pure diamidates (2) listed in Table II were prepared without isolation of the corresponding phosphorodichloridates (1).

Experimental M a t e r i a l s : All melting points are uncorrected.

The hydroxy compounds were of the best quality available. The benzene had been distilled from and

stored over sodium. The ether had been dried over lithium aluminium hydride. Molecular weights were determined isopiestically on a Hitachi Perkin-Elmer Model 115 Molecular Weight apparatus. Elemental analyses were performed on a F & M Scientific Corporation Carbon, Hydrogen, and Nitrogen Analyzer, Model 185.

Preparation of phosphorodichloridates (1) M e t h o d A : P r e p a r a t i o n of c h o l e s t e r y l

p h o s p h o r o d i c h l o r i d a t e (1, R = c h o l e s t e r y l ) . To a solution of 1.02 g (0.0068 mol) phosphorus oxychloride in 5 ml ether was added at 0 °C a solution of 0.68 g (0.0068 mol) triethylamine and 2.58 g (0.0067 mol) cholesterol in 15 ml ether. After 2 h at room temperature, the reaction mixture was filtered. The solid was washed with water to remove triethylamine hydrochloride and air-dried. In this manner was obtained 1.61 g (45%) cholesteryl phosphorodichloridate; m. p. 124-125 °C (dec). Lit.6 '7

m.p. 123 °C.

G . Sosnovsky-M. Konieczny • Preparation of N,N,N',N ,-Bis(ethylene)-phosphorodiamidates 1381

Table II. Preparation of N,N,N/,N/-bis(ethylene)-phosphorodiamidates (2).

1 + 2 HNd R0P(0)(NC])2 t6ll6 a

R0P(0)(N3)2 Yield m.p. with Mol. Wt. Elemental Analysis R 2 [ % ] dec. [°C] (found)

C 3 1 H 5 3 N 2 O 2 P calcd C 72.05 H 10.34 N 5.42 516.754 found C 72.01 H 10.44 N 5.67

Cholesteryl 96 121 (500) C33H57N202P calcd C 72.72 H 10.55 N 5.14 544.808 found C 72.83 H 10.87 N 5.12

/3-Sitosteryl 75 145 (539) /3-Sitosteryl C23H35N2O3P calcd C 66.01 H 8.43 N 6.69 418.520 found C 66.14 H 8.53 N 6.35

Testosteryl 90 64 (404) C16H27N2O7P calcd C 49.23 H 6.97 N 7.18 390.376 found C 49.29 H 7.16 N 7.00

Diacetone-D-glucosyl 85 102 (375) Diacetone-D-glucosyl C 3 3 H 5 7 N 2 O 3 P calcd C 70.68 H 10.24 N 4.99 560.807 found C 70.56 H 10.54 N 4.73

a-Tocopheryl 86 39 (585)

Method B : P r e p a r a t i o n of p h o s p h o r o d i -ch lor idates (1) of cholesterol , ß - s i t o s t e r o l , tocopherol . To a solution of 0.76 g (0.005 mol) phosphorus oxychloride in 10 ml dry ether was added at 0 °C a solution of 0.005 mol of the hydroxy derivative and 0.55 g (0.005 mol) triethylamine in 40 ml dry ether. Following the addition, the reaction mixture was stirred for 2 h at room temperature and filtered. The filtrate was concentrated to 1/5 of its volume and left to stand at — 1 0 °C overnight. The solid dichloridates (1) of cholesterol and /S-sitosterol were obtained in the yields indicated in Table I. Di-chloridate (1) ot tocopherol rapidly darkened upon removal of the solvent and could not be isolated.

Preparation of phosphorodichloridates (1) of diacetone-D-glucose and testosterone

To a solution of 0.76 g (0.005 mol) phosphorus oxychloride in 15 ml dry benzene was added at 8-10 °C a solution of 0.005 mol of the hydroxy derivative and 0.55 g (0.005 mol) triethylamine in 20 ml dry benzene. Following the addition, the reaction mixture was stirred at 8 °C for 1 h, at room temperature for 15 h, and then filtered. Concentra-tion of the filtrate gave the solid dichloridates in the yields indicated in Table I.

Preparation of the N,N,N',N'-bis(ethylene)-phosphorodiamidates (2) without isolation of 1

General procedure : The benzene or ethereal filtrates containing dichloridates (1) (see preceeding

1 O. M. FRIEDMAN, Cancer Chemotherapy Reports 5 1 ( 6 ) , 3 4 7 [ 1 9 6 7 ] .

2 O . M . F R I E D M A N , R . S . L E V I , Z . B . P A P A N A S T A S S I O U , a n d W . M . W H A L E Y , J . M e d . C h e m . 6 , 4 4 9 [ 1 9 6 3 ] .

3 Z . B . P A P A N A S T A S S I O U a n d T . J . B A R D O S , J . M e d . Chem. 5, 1000 [1962].

4 J . C H E Y M O L , P . C H A B R I E R , G . D E Y S S O N , a n d A . CARAYON-GENTIL, Biol. Med. (Paris) 56 (6 ) , 519 [ 1 9 6 7 ] .

experiments) were cooled to 8 °C. To this solution was added rapidly a solution of 1.10 g (0.01 mol) triethylamine in 20 ml benzene. Then was added slowly at 8-10 °C a solution of 0.43 g (0.01 mol) ethyleneimine in 15 ml benzene. Following the addition, the reaction mixture was stirred at 8 °C for 1 h, at room temperature for 15 h, and then filtered. Concentration of the filtrate gave the phos-phorodiamidates (2) in the yields indicated in Table II. Diamidate (2) of tocopherol was obtained as an oil which set to a solid upon storage at — 1 0 °C. Preparation of 2 with isolation of the phosphorodichloridates of cholesterol, ß-sitosterol, testosterone and diacetone-D-glucose

General p r o c e d u r e : To an 8 °C solution of 0.025 mol solid 1 (R = cholesteryl, /?-sitosteryl, testosteryl, and diacetone-D-glucosyl) in 15 ml benzene was added rapidly a solution of 0.55 g (0.005 mol) triethylamine in 10 ml benzene. Then was added slowly at 8-10 °C a solution of 0.22 g (0.005 mol) ethyleneimine in 10 ml benzene. Fol-lowing the addition, the reaction mixture was stirred at 8 °C for 1 h, at room temperature for 15 h, and then filtered. Concentration of the filtrate gave the solid diamidates (2) in yields comparable to those from the reactions without prior isolation of the phosphorodichloridates (1). Due to the instability of tocopheryl phosphorodichloridate, diamidate (2) (R = tocopheryl) could not be prepared by this method.

5 M . D . D O W L I N G , I . H . K R A K O F F , a n d D . A . K A R -NOFSKY, Mechanism of Action of Anti-Cancer Drugs in Chemotherapy of Cancer, pp. 1-74, W. H. COLE (Ed.), Lea and Febiger, Philadelphia 1970.

6 R . J . W . C R E M L Y N , B . B . D E W H U R S T , a n d D . H . WAKEFORD , Synthesis 1971, 648.

7 R . J . W . C R E M L Y N , B . B . D E W H U R S T , D . H . W A K E -FORD, and R . A . RAJA, J . Chem. Soc. Perkin 1 1972, 1 1 7 1 .