AU641363B2

AU641363B2 - Contrast preparation consisting of cavitate- or clathrate- forming host/guest complexes

Info

Publication number: AU641363B2
Application number: AU40651/89A
Authority: AU
Inventors: Celal Albayrak; Georg Rossling; Johannes Tack
Original assignee: Schering AG
Current assignee: Bayer Pharma AG
Priority date: 1988-08-23
Filing date: 1989-08-18
Publication date: 1993-09-23
Anticipated expiration: 2009-08-18
Also published as: DK30391A; ES2042986T3; WO1990001952A1; NO302101B1; NO910711L; AU4065189A; EP0357163A1; DK30391D0; JP3142539B2; GR3005457T3; DE3828905A1; IE65168B1; IE892685L; EP0357163B1; PT91501A; PT91501B; NO910711D0; DE58901585D1; JPH04501559A; ATE76758T1

Abstract

The invention relates to the use of cavity- or clathrate-forming host/guest complexes as contrast media in ultrasonic, X-ray or NMR investigations.

Description

OPI DATE 23/03/90 APPLN. ID 40651 89 AOJP DATE 26/04/90 PCT NUMBER PCT/flFRq/on~L~R

PCT

INTERNATI~jiwu.c AINIVIILUIUV YmmvrrzisL1...11 m"tA..rl UrcivZ izir.w uflri W'IC INTERNATIONALE3 ZUSAMMENARBEIT AUF DEM GEBIET DES PATENTWESENS (PCT) (51) Intematoqialc Patcntklasslflkatlon 5: (11) Intenationale Verliffcntlichungsnumnier: WO 90/101952 A61K 49/00,,,49/04 Al (43) Inernationales ______Veritentlchungsdatum 8, M 4rz 1990 (08,03.90) (21) Internationales Aktenzelchen: PCT/DE89/00548 (74) Auai'ait: MAIKOWSKI, Michael; Xantener Stra~e 10, D- (22) intcrnatlonales Anmeldedatunti: 18. August 1989 (198.889) 10 eln1 D) (30)Prioitltsdaen:(8i) Bestlmmungsstaaten AU, DK, 3JP, NO, US.

P 38 28 905.9 23. August 1988 (23.08.88) -DE Vrfetlh .Mil internationalein Reclicrchenbericlu.

(71) Anmeliler (Afir alle Besdmrnungssfaalcn ausser US), SCH-E- Vor Ablanf derfilr'ideninge: der Ansprldw zisgclasscnen RING AG [DE/DEJ; MtlllerstraBc 170-178, D-100 IBer- Frist Veffiffendilhang wird wiedcrhor falls Anderungen.

liln 65 cinefen.

(72) Erflnderqund Erflnder/Annielder (nurflir US) ALBAYRAK, Celal [Stantenlos/DEJ:, Svenemander Strage 92, D-1000 Berlin ROSSLING, Georg IDE/DE]; Oranienburger gt Chaussee 60 c, D-1000 Berlin 28 TACK, Johannes 616 IDE/DE]; Tharsanderweg 42, D-1000 Berlin 20 1 (54)Title: C-rWRAS.3' PREPARATION CONSISTING OF CAVITATE.- OR CLATHRATE.FORMING HOST/GUEST

COMPLEXES

(54) llezclchnungt MITEL BESTEHEND AUS CAVITATE ODER CLATHRATE BILDENDEN WIRT/GAST..KOMPLE.

XEN ALS KONTRASTM1TTEL (57) Abstract The invention concerns the use of cavitate. or clathrate-forming host/guest complexes as contrast agents for ultrasonic, X.

ray and NMR examinations.

(57) Zusarnmenfassung Die Erfindung betritTt die Verwendung von Cavitate oder Clathrate bildenden \Virt/Gast-Koniplexen als Kontrastniittel be[ Ultrasthall Rdntgen. oder NMR-Untersuchungen.

WO 90/01952 -la- PCT/DE89/00548 Preparation comprising cavitate- or clathrate-forming host/guest complexes as contrast agent The invention relates to a preparation comprising cavitateor clathrate-forming hst/guest complexes in accordance with the preamble of claim 1.

The manufacture of stoichiometric host/guest complexes comprising host molecules, significantly organic onium I compounds and gases or gas formers as guest molecules I has already been described in literature (Angew. Chem. 97 (1985) 721). Use of the host/guest complexes as contrast agents has not been described.

i The invention is based on the problem of providing for ultrasonic, X-ray or NMR investigations a preparation which can be used as a transport medium for contrast agents.

In particular the invention is to provide host/guest complexes eO which store the largest possible guest volume in a minimal host mass.

It has surprisingly been found that the cavitates or clathrates that are indicated in claim 1 form a transport medium which can completely decompose and can thus be chosen so that they do -2not exert any toxic influence on the biological substance in which the investigatio~n is to be carried out.

The preparation used for ultrasonic investigation can advantageously contain as host molecules water, urea and derivatives thereof, thiourea and derivatives thereof, phenol and substituted phehols,-dihydr6xybenzenes and derivatives thereof, hydroquinone and substituted hydroguinones, salicyclic acid and derivatives thereof, tri-o-thymotide and derivatives thereof, ascorbic acid, flavins and derivatives thereof, flavanols and derivatives thereof, cyclophanes and derivatives thereof, guaiacamine, naph-thohydroqui-none and derivatives thereof, cyclodextrin and derivatives thereof, in particular diinethyl-J-cyclodextrin, methyl- f0 -cyclodextrin, hydroxypropyl-6 -cyclodextrin,, chromanes and derivatives thereof, in particular 4-p-hydroxyphenyl- 2,2, 4-triniethylchronane, 4-p-hydroxyphenyl-2 4-trimethylthiochromanej 4-p-hydroplienyl-2 ,l4,7-tetramethylthiochromane, 4-p-h.-ydroxyphenyl-2, 2,4-trimethylselenium chromane, hexahost compoundst in particular hexakis (phenylthio) benzeno and deriw&~ive thereof, cyclotriVeratrylene and derivatives thereof, 1,11binaphthyl-2,2!dicarboxylic acid and derivatives thereof, .8 -3oniuti compounds and derivatives thereof, acetylsalicylic acid, di-, tri- and tetra-salicylides, 9,9'-spirobifluorene- 2,2'-dicarboxylacid, choleic acids, 4-4'dinitrodiphenyl, bis-(N,N'-alkylene-benzidiie), bis-(N,N'-tetranethylenebenzidine)t desoxycholic acid, inonoaminonickel (1I)-cyanide, tetra (4-inethyl-pyridine) -nickel (:i)-dithiocyanates and derivatives thereof, hexarnethylisocyanidoferronchioride, 2-phenyl-3-p(2,2, 4-trimethyl chroman 4-yi)-phenylquinazoline-4, cyclotriph-osphazonest tris-l, 2-phenyldioxycyclotriphosphazones and as guest molecules: inert gaseOs and inert gas compounds, sulphur halides, nitrogen and nitrogen oxides, carbon oxides, hydrogen and hydrogen ,oxides, sulphur oxides, hydrogen phosphides, hydrogen halides, "uraniut. halides and oxygen as well as hydrocarbons and derivatives thereof, epoxides, ether and halogenated hydrocarbons The preparation used for ultrasonic investigation can especially advantageously contain as guest molecules helium# neon, argon, krypton, xenon, radon, sulphur hexafluorid4, water, hydrogen peroxide, nitrogen monoxide, carbon monoxide, carbon dioxide, hydrogen iodide, xenon difluoride, xenon 4 tetrafluoride, xenonhexafluoride, xenon dioxide, sulphur dioxide, sulphur trioxide, arsenic hydride, hydrogen phosphide, deuterium, uranium hexafluoride, methane, ethane, propane, cyclopropane, butane, pentane, ethylene oxide and methyl bromide.

The crystalline complexes can be influenced in their particle size in particular by the crystallisation conditions and also by the mechanical processes of the particle breakdown (air jet grinding).

The crystalline complexes can be coated with hydrophilic lipophilic or amphiphilic auxiliary products.

Suitable vehicles for applying the complexes are sterile aqueous systems with additives to adjust the viscosity, surface tension, pH-value and osmotic pressure wherein the complexes are dissolved, or suspended and optionally emulsified preferably prior to use.

The host/guest complexes are introduced into an aqueous vehicle.

As the host molecules .dissolve the complexes are broken down through the release of the gas bubbles into the vehicle.

5 l- The host molecules dissolved in the vehicle no longer have any complexing properties. The speed of the gas release, and the size and duration of the gas bubbles can be adjusted within a wide range through the type of gas or gas-former enclosed, through the type of host molecule and by the surface or particle size in dependence on the viscosity, surface tension of the vehicle.

It is thus surprisingly possible to obtain in a very simple way injectable, gas-containing pharmaceutical preparations with excellent echogenic properties.

In particular it is possible to prepare the gas volume of about 150 pl required for in vivo contrasting eg of the left ventricle of a human being through very low amounts of active ingredient in the range from 2 lo mg/appln., as shown by the following composition: Hydroquinone/N 2 3:1 Complex 1 mg 70 pl HydroquLnone/Xe 3:1 Complex 1 mg 53 ipl Dianin/SF 6 3:1 1 mg 6 pl Dianin/Argon 2:1 1 mg 26 pl Tri-o-thymotide/methane 2:1 1 mg 23 91 Tri-o-thymotide CH3Br 2:1 1 mg 21 il Dianin/N2 1 mg 103 pi 6 4-(4-hydroxyphenyl)-2,2,4-trimethyl-chromane) is named as the dianin compound and produced according to J. Russ Phys. Chemn. Soc. 46,1310 (1914) and Chem. Zentr. 1915,1,1063.

It is thus possible to prepare a contrast agent for ultras6nic diagnostics which after intravenous application is able to show up the blood and its flow conditions on the right side of the heart and after passing through the pulmonary capillary bed on the left side for ultrasound. Furthermore it also is to show the circulation to other organs, such as the myocardium, liver, spleen and kidneys. It can similarly be used to show the urinary ducts, gastro-intestinal tract, joints, frontal sinus and eyes.

Particularly when using gas molecules (eg xenon) which are able to overcome the blood/brain barrier, it is also possible to show the cerebrum and its physiological and pathological structures through ultrasound.

If the preparation according to the invention also contains eg xenon then it is possible to use this host/guest complex as an X-ray contrast agent. When using stable radicals (eg oxygen-, nitroxyl-) the pteparations according to the invention can also be used as NMR-contrast agents.

7 The invention will now be explained by the following examples.

1. Tri-o-thymotide/methyl bromide Tri-o-thymotide k25g) was dissolved in 2,2,4-trimethylpentane at loo OC and the hot solution was introduced into the high pressure autoclave. Methyl bromide-, as added to the autoclave until a pressure of 200 bar was reached. The high pressure autoclave was then kept for 2 hours at 110 0

C

and the solution was then cooled down to room temperature within 5 days. The crystals were filtered off and washed 3 times .ith cold 2,2,4-trimethylpentane. The crystals were t en dried in the drying cabinet at 2. Dianin-compound (4-p-hydroxyphenyl2,2,4-trimethylchromane)/ ethylene oxide Dianin compound (25g) was dissolved in l-docanol (35 g) at 325° C. The hot solution was introduced into the high pressure autoclave. The solution was subjected to compressed ethylene oxide of 3oo bar. The high pressure autoclave was kept for 2 hours at 140 0 C and the solution then cooled down to room temperature 8 within 8 days. The crystals were filtered off and washed 4 times with cold 1-decanol (5mi) The crystals were then dried in the drying cabinet at 100 0

C.

3. Dianin-compound (4-p-hydroxyphenyl)-2,2,4-trimethylchromane/sulphur hexafluoride Dianin compound (25g) was dissolved in 1-decanol, at 125, 0 C. The hot solution was introduced into the high pressure autoclave. The solution was subjected to compressed sulphur hexafluoride of 3oo bar. The high Pressure autoclave was tempered for 2 hours at 14o 0 C. The sblution was then cooled down to room temperatoure within 8 days.

T;Ae crystals were filtered off and washed 4 times with cold Idecanol The crystals were subsequently dried in the drying cabinet at 100 0

C.

4. Dianin-compound (4-p-hydroxyphenyl-2 7 2 4-trirnethylchromane) /ethanc Dianin-compound (25 q) was dissolved in 1-decar~ol (359) at 125 0 C. The hot solution was introduced into the high pressure autoclave. The solution was subjected to compressed ethane 9of 300 bar. The high pressure autoclave was kept for 2 h at 140 0 C. The solution was then cooled down to room temperature within 8 days. The crystals were filtered off and washed 4 times with cold 1-decanol Then the crystals were dried in the drying cabinet at 100 0 c.

Diaxn4n-compound (4-p-hydroxyphenyl-2. 2,4-trimethylchromane) /propane DJianin compound (25g) was dissolved in 1-decanol (35 g) at 125 0 C. The hot solution was introduced into the high pressure autoclave. The solution was subjected to compressed propane of 300 bar. The high pressure autoclave was kept *for 2 h at 140 0 C. The solution was then cooled down to room temperature within 8 days. The crystals were filtered off and washed 4 times 'with cold 1-decanol (S ml). The crystals were then dried in the drying cabinet at 100 0

C.

6. Di1anin-compound (4-p-hyaroxyphony.-2 2, 4-trimeothylchromane) /carbon dioxide Dianin-compound (25 g) was dissolved in 3-decanol '0 i 10 at 125°C. The hot solution was introduced into the high pressure autoclave. The solution was subjected to compressed carbon dioxide of 300 bar. The high pressure autoclave was kept for 2 h at 140 0 C. The solution was then cooled down to room temperature within 8 days. The crystals were filtered off and washed 4 times with cold 1-decanol (5 ml).

The crystals were then dried in the drying cabinet at 100 0

C.

7. Dianin-compound (4-p-hydroxyphenyl-2,2,4-trimethylchromane/cyclopropane Dianin-compound (25 g) was dissolved in 1-decanol (35 g) at 125 0 C. The hot solution was introduced into the high pressure autoclave. The solution was subjected to compressed cyclopropane of 300 bar. The high pressure autoclave was kept for 2 h at 140 0 C. The solution was then cooled down to room temperature within 8 days. The crystals were filtered off and washed 4 times with cold 1-decanol (5 ml).

The crystals were dried in the drying cabinet at 100 0

C.

8. Dianin-compound (4-p-hydroxyphenyl-2,2,4-trimethylchromane)/methane Dianin-compound (25 g) was dissolved in 1-decanol (35 g) at 11 12500C. The hot solution was introduced into the high pressure autoclave. The solution was subjected to compressed methane of 300 bar. The high pressur/ autoclave was kept for 2 h at 1400C. The solution wa' hen cooled down to room temperature within 8 days. The crystals were filtered o~ff and washed 4 times with cold 1-docanol (5 ml) The crystals were dried in the drying ca.binet at 100 0

C.

9. Dianin-conipound (4-p-hydroxyphenyl-2, 2, 4-trimethylchromacne) /nitrogen Dianin-compound (25 g) was dissolved in I-decanol (35 g) at 125 0 C. The hot solutjon was introduced into the high pressure autoclave. The soldtion was subjected to compressed nitrogen of 300 bar. The high pressure autoclave. was kept for 2 h at 140 0 C, The solution was then cooled down to room temperature within 8 days. The crystals were filtered off and washed 4 timnes with cold Idecaui (S ml). The crystals were then dried in the drying cabinet at 100 0

C.

Malting point: 162.8eoC, 1.2 lo. Dianin-compound (4-p-hydroxyphenyl-2,2, 4-trimethylchromane) /xenon Dianin-compound (25 g) was dissolved in 1-decanol (35 g) at 125'C. The hot solution was introduced into the high pressu~re autoclave. The solution was subjected to compressed xenon of 300 bar. The high pressure autoclave was kept for 2 h at 1.40 0 C. The solution was then cooled down to room temperature within 8 days. The crystals were filte' ed off and washed 4 times with cold 1-decanol (5 ml).

The crystals were then dried in the drying cabinet at 100 0

C.

11. Di anin- compound, (4-p-hydroxyphenyl-.2r27 4-trimethylchromane) /argon Dianin-compound (25 g) was dissolved in l-dicano. (35 g) at 125 0 C. The hot solution was introduced into the high pressure autoclave, The solution wag subjected to compressed argon of 300 bar. The high pressure autoclave was kept for 2 h at 140 0 C. The solution was then cooled down to room temperature within 8 days. The crystals were filtered off and washed 4 times with cold 1-decahol (S Ml) *The 13 crystals were then dried in the drying cabinet at 100 0

C.

Melting point: 160.84 0

C.

12. Hydroquinone/methane Hydroquinone (30 g) was dissolved in n-propanol (70 ml) at 70°C. The hot solution was introduced into the high pressure autoclave. The solution was subjected to compressed methane of 300 bar. The high pressure autoclave was kept-for 2 h at 80 0 C. The solution was then cooled down to room temperature within 5 days. The crystals were filtered off and then washed 4 times with cold i-propanol ml). The crystals were dried in the dying cabinet at subsequently.

13. Hydroquinone/sulphur hexafluoride Hydroquinone (30 g) was dissolved in n-propanol (70 ml) at The hot solution was introduced into the high pressure autoclave. The solution was subjected to compressed sulphur 4 14 hexafluoride of 300 bar. The high pressure autoclave was kept for 2 h at 80 C. The solution was then cooled down to room temperature within 5 days. The crystals were filtered off and washed 4 times with cold n-propanol ml). The crystals were then dried in thedrying cabinet at 70 0

C.

14. Hydroquinone/propane Hydroquinone (3o g) was dissolved in n-propanol (70 ml at 70°C. The hot solutibn was introduced into the high pressure autoclave. The solution was subjected to compressed propane of 300 bar. The high pressure autoclave was kept for 2 h at 800C. The solution was then cooled down to room temperature within 5 days. The crystals were filtered off and washed 4 times with cold n-propanol 5 ml), The crystals were then dried in the drying cabinet at 70 0

C.

Hydroquinone/ethane Hydroquinone (30 g) was dissolved in n-propanol 70 ml) at 70 0 °C The hot solution was introduced into the high 15 pressure autoclave. The solution was subjected to compressed ethane of 300 bar. The high pressure autoclave was kept for 2 h at 80 0 C. The solution was then cooled down to room temperature within 5 days. The crystals were filtered off and washed 4 times with cold n-propanol ml).Then thecrystals were dried in the drying cabinet at 70 0

C.

16. Hydroquinone/carbon dioxide Hydroquinone (30 g) was dissolved in n-propanol (70 ml) at C. The hot solution was introduced into the high pressure autoclave. The solution was subjected to compressed carbon ,z dioxide of 300 bar. The high pressure autoclave was kept for 2 h at 80 C.Then thesolution was cooled down to room j temperature within 5 days. The crystals were filtered off and washed 4 times with cold n-propanol 5 ml). The crystals were then dried in the drying cabinet at 700C.

17. Hyd oquinone/ethylene oxide Hydroquinone (30g) was dissolved in n-propanol (70 ml) at 16 The hot solution was introduced into the high pressure autoclave.' The solution was subjected to compressed ethylene oxide of 300 bar. The high pressure autoclave was kept for 2 h at 80°C. The solution was then cooled .down to room temperature within 5 days. The crystals were filtered off and washed 4 times with cold n-propanol ml). The crystals were then dried in the drying cabinet at 70 0

C.

18. Hydroquinone/cyclopropane kydroquinone (30 g) was dissolved in n-propanol (70 ml) at The hot solution was introduced into the high pressure autoclave. The solution was subjected to compressed cyclopropane of 300 bar. The high pressure autoclave was kept for 2 h at 80 0 C. The solution was then cooled down to room temperature within 5 days. The crystals were filtered off and washed 4 times with cold n-propanol (5 ml).

The crystals were then dried in the drying cabinet at 19. Hydroquinone/nitrogen 4 I 17 Hydroquinone (30g) was dissolved in n-propanol (70 ml) at 70 0 C. The hot solution was introduced into the high pressure autoclave. The solution was subjected to coUpressed nitrogen of 300 bar. The high pressure autoclave was kept for 2 h at 80 C. The solution was then cooled down tio room temperature within 5 days. The crystals were filtered off and washed 4 times with cold n-propanol ml). The crystals were dried in the drying cabinet thereafter at 700 C.

Melting point 176.92 0

C.

Hydroquinone/xenon Hydroquinone (30g) was dissolved in n-propanol (70 ml) at The hot solution was introduced into the high pressure autoclave. The solution was subjected to compressed xenon of 300 bar. The high pressure autoclave was kept for 2 h at 800C The solution was then cooled down to room temperature within 5 days. The crystals were filtered off and washed 4 times with cold n-propanol (5 ml). The crystals were then dried in the drying cabinet at 70 0

C.

18 21. Hydroquinone/argon Hydroquinone (30 g) was dissolved in n-propanol (70 ml) at C. The hot solution was placed in the high pressure autoclave. The solution was subjected to compressed argon of 300 bar. The high pressure autoclave was kept at 80 0

C

for 2 h The solution was then cooled down to room temperature within 5 days. The crystals were filtered off and washed 4 times with cold n-propanol 5 ml). The crystals were then dried in the drying cabinet at 70 0 c.

Melting point 175.67°C.

22. Urea/butane 4 g urea were dissolved iti 12 %1 ethanol at 60°C. The solution was then placed in an high pressure autoclave and subjected to a butane pressure of 150 bar. The solution was cooled down from 60 0 C to room temperature within 48 h.

The solution with h/g crystals was removed from the autoclave, filtered and the h/g crystals were washed with ml cold ethanol. The h/g complex crystals were dried in the vacuum cabinet at 60 0

C.

19 23. Urea/isobutane 4 g urea were dissolved in 12 ml ethanol at 60 0 C. The solution was then placed in a high pressure autoclave and subjected to an isobutane pressure of 150 bar.

The solution was cooled down from 60 0 C to room temperature within 48 h. The solution with h/g crystals was removed from the autoclave, filtered and the h/g crystals were washed with 10 ml cold ethanol. The h/g complex cystals were dried in the vacuum cabinet at 60 0 c.

Melting point: 138.50 oC.

24. Urea/neopentane 4 g urea were dissolved in 12 ml ethanol at 60 0 C. The solution was then placed in a high pressure autoclave and subjected to a neopentane pressure of 150 bar. The solution was cooled down from 60°C to room temperature within 48 h.

The solution with h/g crystals was removed from the autoclave, filtered and the h/g crystals were washed with 10 ml cold ethanol. The h/g complex crystals were dried in the vacuum cabinet at 60 0

C.

Melting point: 138.79 0

C.

Thiourea/butane 4 g thiourea were dissolved in 12 ml ethanol at 60 0

C.

The solution was then placed in a high pressure autoclave and subjected to a butane pressure of 150 bar. The solution was cooled down to room temperature within 60 h. The solution with h/g crystals was removed from the autoclave, filtered and the h/g crystals were washed with 10 ml cold ethanol..

The h/g complex crystals were dried in the vacuum cabinet at 60 0

C.

26. Thiourea,.,4sobutane 4'gthic urea were dissolved in 20 nml ethanol at 60 0

C.

The solution was then placed in a high pressure autoclave and subjected to an isobutane pressure of 150 bar. The solution was cooled down to room temperature within G0 h.

The solution with h/g crystals was removed from the autoclave, f14tered and the h/g crystals were washed with 10 ml, cold ethanol.

The' h/g complex crystals were dried in the vacuum cabinet at 0C.

Melting point: 181.34 0

C.

21. 27. Thiourea/neopentane 4 g thiourea were dissolved in 20 ml ethanol at 600C.

The solution was then placed in a high pressure autoclave and subjected to a neoperitane pressure of 150 bar. The solution was cooled down to room temperature within 60 h. The solution with h/g crystal,, was removed from the autoclave, filtered and the h/g crystals were washed with 10 ml cold ethanol. The h/g complex crystals were dried in the vacuum cabinet at 60 0

C.

28. Vehicle A: The following solutions for example are suitable as a vehicle for hydroquinone-I tri-0-thymotide-urea- and thiourea-h/g complexes: a) 1 S gelatine solution b) I S albumin solution c) 10 glycerin solution d) 15 S propyltne glycol solution e) Mixtures of sodium cholate and phosphatidyicholino in water f) 0.01 1 phosphatidylcholine dispersion (aqueous) g) 1 methyl celluloge h) 1 -2 %dextran solution 22 i) 1 agar solution J) 2 "Tween'solution (Tween k) I gum arabic Bt The following vehicles are suitable for dianin-h/g-complexes, for example: a) 10 20 S 2-(2-inethoxyethoxy)-ethanol b) Mixtures of 2 (2 rethoxyethoxy)-ethanol (20 %)and 'Tweeno (1 In vitro ultrasonic investigations The acoustic properties of the h/g complex-vehicle systems were determined wit1% in-vitro ultrasonic investigjations.

ror this about I S mg of the h/9 em~pPexes were mixed in ml with one of tha said vehicles and thczt -,xaimined with ultrasonic scanners.

SL 23 The ultrasonic scanner Ekoline 20A/S was used in the frequency range 1 5 MHz for qualitative examinations.

Quantitative measurements of the acoustic properties were obtained in an apparatus with the ultrasonic scanner Kraut- Kraemer U.S.I. P-12 at 4 Mlz. The results of four systems are detailed here by way of example (Figs. 1 4).

Fig. 1: Urea/isobutane (Example 23) in 2 %"Tween 80 solution Fig. 2: Thiourea/isobutane (Example 26) in 1% dextran solution Fig. 3: Hydroquinone/argon (Example 21) in 1 gelatine solution Fig. 4: Dianin/argon (Example 11) in 10 2 (2-methoxyethoxy)ethanol To explain the ultrasonic measuring apparatus and the diagrams obtained therefrom: The apparatus comprises an ultrasonic transmitter combined with a receiver and measuring bulb which contains the specimen.

An ultrasonic impulse is transmitted to measure the acoustic properties of the specimen. Reflected ultrasound is measured 24 by the receiver and indicated through a change in the amplitude (see diagram). The diagrams each only show one amplitude change which results from the reflection of the ultrasound from the front wall of the measuring bulb. A second amplitude change which results from reflection from the back wall of the measuring bulb is only obtained with non-echogenic substances (eg water).

In the case of echogenic substances a second reflected signal is not obtained since the ultrasound is dissipated in the specimen or changed so that it can no longer be received.

Claims

1. A preparation for use as an injectible contrast agent in ultrasonic, X-ray or NMR investigations, said preparation comprising a pharmaceutically acceptable fluid, v.hicle and a cavitate- or clathrate-forming host/gucst complex which, when dissolved in said fluid vehicle relcases the gucst moleculcs from the host molecules as the host dissolves in said fluid vehicle, said guest molecules functioning as the contrast agent, 41 1) 2. The preparation according to claim 1, wherein said host Is selected from any one of water, urea and derivatives thercof, thiourea and derivatives thereof, phenol and substituted phenols, dihydroxyberizcnes and derivatives thereof, hydro-quinione and substitute hydroqulniones, salicylic acid and derivatives thereof, tri-o-thymotide and derivatives thereof, ascorbic acid, ilvins and derivatives thereof, flavanols and derivatives thereof, cyclophan4 and derivatives thereof, gualacanilne, naphithohydro-qluinones and derivatives thereof, chromatics and derivatives theveof, Including 4-p-hy droxyphienyl-2,2,4- trhet~fcromnc 4--hyroyphny-2,2,4-trlmethiylthiioehronitane,

4-p-hydroxyphietyl- 2,2,4,7-tetrainethylth iochromane, 4-lIydroxypentyl-2,2,4-trieitliyls ,.3cniuin chronatic, hexaliolt compounds, including hexakis (phenylthio),ben',.cne and derivatives thereof, cyclotriveratrylene and derivatives thereof, 1,1P-binaph~lthiyl.2,2'-dicarboxyllc acid aInd derivatives thereof, onlurn compounds and derivatives thereof, aetylsalicylic acid, di-, tri- and tctrasahicylides, 9,9'-spirobifluorcne-2 ,2'-dicarboxylacid, choleic acids, 4,4'- dinitrodiphenyl, bis(N,N1-alkylenabenzldine), bis(N -tetranttiethlylcnicbetnzidlnie), or desoxycholic acid, nionoandijonlckol (11) -cyanide, tetra- (4-niethyl pyridieo) nickel (11) di thiocyanats and derivativesthereof, hexamethylisocyaidofe rron-ch lorides, 2-phe nyl-3-p-. (2,2,4-tritnctliylchiromin4-y-)'phe tultazolne-4, cyclotriphospitazone, tri.-s-1 ,2- 1lthenyldioxycyclotriphosliazones, or inixtures thereof, And saki guest Is selected from Inert gases and inert gas compounds, sulphur halides, nitrogen and nitrogen oxides, carbon *~,,oxides, hydrogen and hydrogen oxides, sulphur oxides, hydrogen phosphides, hydrogen halides, wirn halides ane, oxygen as well as hydrocarbons and derivatives thereof, T:epoxides, eithers and halogenated hydrocarbons, or mixtures thereof. S I 330ovtMAU 4 3. The preparation according to claim I. or claim 2 wherein said host so selected from any one of: hydroquinone, dianin, urea, thiourcai, or tri-o-thymotide, 4. The preparation according to any one of claims 1 to 3, wherein said guest is selected from any one of: helium, neon, argon, krypton, xenon, radon, sulfur hexafluoride, water, hydrogen. peroxide, nitrous oxide, carbon monoxide, carbon dioxide, hydrogen iodide, xenon difluoride, xenon tetrafluoride, xenonhexa fluoride, xe-non dioxide, sulfur dioxide, sulfur trioxide, arsenic hydride, hydrogen phosphide, deuterium, uranium hexafluoride, methane, ethane, propane, cyclopropane, butane, pentane, and the isomers thereof, ethylen, oxide and methyl bromide. or mixtures thereof. S. The preparation according to claim 4 particularly for use in ultrasonic investigations, whereby said guest is selected from any one of: *too nitrogen, xenon, argon, sulfur hexafluoride, methane, ethane, propane, butane, isobutane, pentane, neopentane, cyclopropane, inethyibromide, ethyleneoxide, carbon dioxide, or the mixtures thereof.

6. The preparation according to clhum 4 particularly for use in X-r investigations, whereby said guest Is selectced fronm oxygen or nitrous oxide.

8. The preparation according to any one of claims 1 to 7 wherein said fluid vehicle Is primarily sterile water or 2-(2-itnethoxyethuoxy)-ethutnol.

9. The preparation according to claim 8 which contains one or inore additives. to adjust the viscosity, surface tension, p11, or osmotic pressure of the preparation, The preparation according to claim 9, wllercin~lsaltd additive is selected froIII Z" onle of more of: gelatin, albumin, glycerin, propylene glycol, so 3iuib cholate, phosphatidyleholine, Methyl cellulosc, dextran, agar, a surfactant, gum arabih or,2-(2 -i-ethoxyethioxy)-ethainol,

11. A preparation for use as an injectable contrast agent in ultrasoric, X-ray or NMR investigations, substantiotlly- as hierein ,described with reflreuco to any Olt" of Examples I to 27.

12. A method for tile preparation of an Injectib 1 contirast media which is to be used in ultrasonic, X-ray, or NMR investigations, said :nel~hod comnprikilng dissolving at cavitate- or clathrate- forming host/guest complex in a phartmceutically Vcceptalble fluid vehicle, the host by dissolving, releasing tile guest which func(t' kils as a contrast agent. 13, The method according to claim 12 wherein 4 ald host is selected from any one of' water, urea and derivatives thereof, thiourea and deriv4 \tivcs thereof, phenol and substituted phnl, dihydroxyben7.enes and derivatives thereo~f, hydro-quinone and substitute hydroquiniones, salicylic, acid and derivatives tliercot, tri-o-thyniotide and derivatives thereof, ascorbic acid, Ilavins ,and derivatives thereof, flavanols and derivatives thereof, cyclophane and derivatives thereof', guaiacamine, naphithohydro-quitiones and derivatives thereof, chromanes and derivatives thereof, more particularly 4-p-hydroxyphenyl-2,2,4- 0 a 6 totrimethylchromanc, 4-pdiydroxyplhcnyl-2,2,4-trimeithiylthiiochironte, 4-p. hydroxyplhenyl- 2,2 ,4,7-tctramcithiylthiiochironiane, 4-p-hiydroxyphienyl-2;,2,4-trimeithiylseleniuni chromane, hexahost compounds, more particularly hexakis (phenyithia) berivcne and derivatives 0thtereof, cyclotriverairylene anidderivaitives thereof, 1,1' Ibinaph~lthtyl-2,2' -dicarb~oxylie acid and derivatives thereof, onitim compounds and derivatives thereof, acetylsalicylic acid, di-, tri- and tetrasalicyl ides, 9,9'-spirobifluorcnec-2,2'-dicarboxyla.tid, choleic, acids, 4,4'- dinitrodiphienyl, bis(N ,N'-alkyleniceezidinec), s(N-traehyebezdn) .:desoxycholie acid, inonoamlnonickel (11) -cyanide, tetra- (4-inethyl py rid! ne) nickel (11) too dithiocyanatesandderivatvshroleachlscaidfro.hoic,-hnl3p (2,2,4-trimcthiylchroman-4-yI)-phcenylquinazolinie-4, cyclotriphosphazonc, tris-1 ,2- phenyldioxycyclotriphosphazones, or mixtures thereof, and said guest is selected from inert gases and inert gas compounds, sulphur halides, nitrogen and nitrogen oxides, carbon oxides, hydrogen and hydrogen oxides, sulphur oxides, hydrogen phosphides, hydrogen halides, uranium halides and oxygen as well as hydrocarbons and derivatives thereof, epoxidcs, ethers and halogenated hydrocarbons, or mixtures thereof. 14, The method according to claim 13 said host so selected from any one of: hydroquinone, dianin, urea, thiourca, or tri-o-thymotide. The method according to claim 14 wherein said guest 1i selected from any one oft. helium, neon, argon, krypton, xenon, radon, sulfur hexafluoride, water, hydrogen peroxide, nitrous oxide, carbon monoxide, carbon dioxide, hiydrogen iodide, xenon 4' difluorlde, xenon tetraflu oride, xenonheoxafluoride, xenon dioxide, sulfur dioxide, sulfur trioxide, arsenic hydride, hydrogen phiosphide, deuteriunm, uranium licxafluoridc, mctiiane, 0 Os ethane, propane, cyclopropane, butane, pentane, and the isomners thereof', ethylene oxide1 and methyl bromide or mixtures thereof.

16. The method according to claim 15 particularly for use in ultrasonic investigations 4 4 whereby said guest is selected from any one oft nitrogen, xenon, argon, sulfur hexafluoride, methane, ethane, propane, butane, isobutane, pentane, neopentane, ay .loprupane, methyibromide, ethyleneoxide, Carbon dioxide, or,,the mixtures thereof, 2 iJf

17. The method according to claim 16 particularly for use in X-ray Investigations. whereby said guest ixenon.

18. The method according to claim 17 particularly for use In NMR Investigations, 29 W~hereby said guest is selectcd from oxygen or nlitrous oxide.

19., The method according to claim 18 whecrein said fluid vehicle is primarily sterile water or 2-(2-methioxyethoxy)-ethanol. The method according to claim 19 wvhich conta ins one or morc additives to adjust the viscosity, urfaca tension, pH, or osmotic pressure of the preparation.

21. Theo method according to claim 20 wherein said additive is selected from any one or more of: gelatin, albumin, glycerin, propylene glycol, sodium cholate, phosphatidylehioline, 0o methyl cellulose, dextran, agar, a surfactant, gumi arabic, or 2-(2-methoxycthioxy)-ethanttol,

22. A method for the preparation of an injectibie, contrast media, said method sbstantially ats herein described with reference to the "in vitro ultrasonic Investigation" S ampie and Its associated drawings. Y 23. A method for conducting an ultrasonic, X-ray or NMR Investigation of a subject using a contrast agent, characte rived in that at preparation according to at, ono of claims $too% I to 11 is prepared and injected into said subject ait a suitable location lit mid subject and in a sufficient amount to provide contrast. DATED this I3day of July 1993, SCIIERING ATicrENGESELLSCIIAFr gy their P~atent Attorneys DAVIES COLILISON CAVE