NO130670B - - Google Patents

Description

Protective agent against

ultraviolet radiation.

The protective effect of the hitherto known light protection agents is due to the fact that they keep the erythema-producing ultra-violet rays from the sun (between 290 and 320 nm) away from the living epidermis cells by specific absorption (actually a UV B filter) or by scattering or reflection, such as with covering preparations such as zinc oxide.

It was now surprisingly found that cytosine, uracil, guanine and 5-chloro-uracil, although they do not cover like a powder or the absorption maximum is between 290 - 320 nm, have a distinct protective effect against the radiation. The light protection effect is also more pronounced with a stronger erythema than with a weak erythema or the lack of such. With normal, absorptive-acting light protection agents, this condition cannot be established.

The present invention is based on these findings and relates to a protective agent against ultraviolet radiation which is characterized by the fact that it contains as active compounds cytosine, uracil, guanine and/or .5-chloro-uracil in a total concentration of active compounds of 1-30 %, preferably 2-5%, and optionally a further common light protection agent.

The aforementioned compounds have the following formulas:

Any common preparation that meets the cosmetic requirements can be used as a basis for the product, e.g. creams, ointments, jellies, oils, solutions or sprays. However, the light protection effect is, as also with the usual ones, i.e.

with specifically absorbing filters produced light protection agents, depending on the basis used. The intensity of the light protection effect also depends on the same basis on the active substance concentration. Suitable concentrations are between 1-30%, preferably between 2-5%.

The substances that can be used according to the invention can also be combined with other common light protection agents, as a potentiation of the light protection effect, i.e. a synergistic effect occurs. Conventional light protection agents generally mean such organic compounds whose absorption maximum lies between 290 and 320 nm. As this filter property is peculiar to many organic compounds, compounds from the most diverse classes of substances, of which only a few will be mentioned here, can be combined with the light protection agent according to the invention.

1) Derivatives of p-aminobenzoic acid, such as e.g. ethyl p-aminobenzoate and other esters, such as e.g. propyl, butyl

and isobutyl-p-aminobenzoate. Ethyl-p-dimethylaminobenzoate, glyceryl-p-aminobenzoate, amyl-p-dimethylaminobenzoate: 2) Derivatives of cinnamic acid, such as e.g. 2-ethoxyethyl p-methoxycinnamic acid ester, ethylhexyl p-methoxycinnamic acid ester, p-methoxycinnamic acid ester mixtures and cinnamic acid ester mixtures.

3) Dibenzalhydrazines.

4) Derivatives of 2-phenylbenzimidazole such as e.g. 2-phenylbenzimidazole-5-sulfonic acid. 5) Derivatives of salicylic acid, such as e.g. salicylic acid menthyl ester, salicylic acid homomentyl ester and salicylic acid phenyl ester. 6) Derivatives of benzophenone, such as 4-phenylbenzophenone, 4-phenylbenzophenone-2-carboxylic acid isooctyl ester and 5-chloro-2-hydroxybenzophenone. 7) Derivatives of coumarin, such as e.g. 7-oxycoumarin, (3-umbelliferoneacetic acid and 6,7-dioxycoumarin. 8) Derivatives of gallic acid, such as e.g. digalloyl trioleate. 9) Dehydracetic acid (3-acetyl-6-methyl-1,2-pyran-2,4-dione). 10) Derivatives of quinoline, such as e.g. the sodium salt of 8-ethoxyquinoline-5-sulfonic acid. 11) Derivatives of anthranilic acid, such as e.g. anthranilic acid menthyl ester.

12) Hydroxyphenylbenztriazole.

The testing of the light protection effect takes place by determining the "average protection factor" according to Schulze (Parfumerie und Kosmetik 37, 310/365 (1956). For this purpose, the back skin of the subject is divided with adhesive plasters into horizontal skin strips. On every other strip of skin, always apply the same person a preparation, while they

other strips remain untreated as a control. So up-

read by vertical plaster strips all skin areas for 8 approx.

1 cm 2 large fields and the remaining skin are uncovered with pieces of cloth. The test area is then illuminated with a group of 4 Osram ultra-vitalux lamps, which had previously burned in for at least 5 minutes, at a distance of 40 cm and the vertical field lines are revealed from left to right after increasing illumination time. As time, the geometric series 1, 1.4, 2, 2.8 minutes etc. is chosen, with the irradiation ending after 11.2 or 16 minutes.

All plasters are then removed and the erythema threshold time is read 24 hours later.

In addition, the vertical rows are numbered and for each horizontal row it is determined in which case an erythema is precisely recognisable. The reading takes place by switching the order of the preparations on the back of every other sample individual as the reader dictates the results for the test protocol.

From the test protocol, the protection factor is calculated

for the preparation in question and the patients in question according to the equation:

With this method, 20 adults of different age, gender and skin type are examined for each preparation and from the 20 individual values the average protection factor is calculated for the preparation in question as an arithmetic mean.

'RESULTS

The data below illustrate the synergistic effect between guanine and a common light protection agent

The light protection factor was measured according to the previously stated method by Schulze.

The preparations are produced as follows:

EXAMPLE 1

5.80 g (0.0385 mol) of guanine (2-amino-6-hydroxy-purine) is dissolved hot in a mixture of 56.7 g of distilled water, 11.5 g of 1,2-propanediol and 1 ml of concentrated ammonia solution At 75°, this solution is added to a fat phase also heated to 75° consisting of 15.0 g of stearyl alcohol, 5.0 g of white vaseline and 5 g of a polyoxyethylene stearyl ether (BriJ 76) while stirring. After cooling, it is thus scraped off formed cream even over

a wooden roller chair and filled in tubes.

In an analogous way, a solution of

a) 4.27 g (0.0335 mol) cytosine in 53.23 g distilled water, 11.5 g 1,2-propanediol and 6.0 g lactic acid b) 5.62 g (0.0335 mol) 5- Flax uracil in 56.35 g distilled water, 11.5 g 1,2-propanediol and 1.53 g sodium hydroxide c) 4.51 g (0.0385 mol) uracil in 56.19 g distilled water, 11.5 g 1,2-propanediol and 3 g lactic acid,

processed into an ointment.

EXAMPLE 2

2.0 g (0.0133 mol) guanine is dissolved hot in a mixture of 60.7

g of distilled water, 11.5 g of 1,2-propanediol and 0.8 g of sodium hydroxide. At 75°C, this solution is added to a fat phase also heated to 75°C consisting of 13.0 g of stearyl alcohol, 5.0 g of white vaseline, 5.0 g of polyoxyethylene stearyl ether and 2.0 g of 2-ethoxyethyl-p-methoxycinnamic acid ester under rowing. After cooling down

the cream thus formed is scraped over a wooden roller and filled into tubes.

EXAMPLE 3

An ointment containing guanine and cytosine as active ingredients was prepared as follows: 3 g (0.0200 mol) of guanine and 2 g (0.0180 mol) of cytosine were dissolved in a warm mixture of 57.5 g of distilled water , 11.5 g of propylene glycol and 1 ml of concentrated ammonia solution. At 75°C, the resulting solution was added with stirring to a hot (75°C) mixture of 17.0 g of stearyl alcohol, 4.0 g of white petroleum jelly and 4.0 g of a polyoxyethylene stearyl ether ("Brij J"). Lactic acid was added immediately to neutralize the emulsion, i.e. bring the pH of the emulsion down to approximately the pH of the skin, which is approx. 5.5. After cooling, the resulting cream was further processed using a wooden rolling frame and filled into tubes.

EXAMPLE 4

An ointment containing guanine, 5-chloro-uracil and uracil was prepared as follows: 2.0 g of guanine, 2.81 g of 5-chloro-uracil and 2.26 g of uracil were dissolved in a hot mixture of 53, 93 g of distilled water, 14 g of propylene glycol and 1 ml of concentrated ammonia solution. At 75°C, the resulting solution was added with stirring to a hot (75°C) mixture of 17.0 g of stearyl alcohol, 4.0 g of white petroleum jelly and 4.0 g of a polyoxyethylene stearyl ester ("Brij J"). Lactic acid was added immediately to neutralize the emulsion, i.e. to bring the pH of the emulsion down to approx. pH for the skin, which is approx. 5.5. After cooling, the resulting cream was further processed using a wooden rolling frame and filled into tubes.

EXAMPLE 5

1.42 g (0.0128 mol) of cytosine was dissolved in a warm mixture of 61.28 g of distilled water, 11.5 g of propylene glycol and 0.5 g of sodium hydroxide. At 75°C, the resulting solution was added with stirring to a hot (75°C) mixture of 13.0 g of stearyl alcohol, 5.0 g of white petroleum jelly, 5.0 g of polyoxyethylene stearyl ether and 2.0 g of 2-ethylhexyl-p -methoxycinnamate. Lactic acid was added immediately to neutralize the emulsion, i.e. bring the pH of the emulsion down to the pH of the skin, which is approx. 5.5. After cooling, the resulting cream was further processed using a wooden rolling frame and filled into tubes.

EXAMPLE 6

1.87 g (0.128 mol) of 5-chloro-uracil was dissolved in a warm mixture of 60.83 g of distilled water, 11.5 g of propylene glycol and 0.8

g of sodium hydroxide. At 75°C the resulting solution was added with stirring to a hot (75°C) mixture of 13.0 g

stearyl alcohol, 5.0 g white petroleum jelly, 5.0 g polyoxyethylene stearyl ether and 2.0 g amyl p-dimethylamino benzoate. Lactic acid was added immediately to neutralize the emulsion, i.e. bring the pH of the emulsion down to the pH of the skin, which is approx. 5.5. After cooling, the resulting cream was further processed using a wooden rolling frame and filled into tubes.

EXAMPLE 7

A radiation shielding agent in aerosol form with the following composition:

was produced as follows:

A mixture of 18.0 g isopropyl myristate, 30.0 g stearic acid, 9.0 g myristic acid and 18.0 g glycerin was melted at 75°C - 80°C. An already heated (75°C) mixture of 440.0 g of water, 20.0 g of triethanolamine and 12.0 g of cytosine was added dropwise at 75°C with vigorous stirring to this mixture. After cooling the resulting mixture to 50°C, 6.0 g of panthenol, 3.0 g of perfume and 12.0 g of ethylhexyl-p-methoxy-cinnamate were added. Lactic acid was added immediately to neutralize the emulsion, i.e. bring the pH of the emulsion down to the pH of the skin, which is approx. 5.5. The resulting emulsion was cooled with stirring to 20°C and 90.0 g of this emulsion was mixed in aerosol containers with 10 g of a propellant (40 dichlorodifluoromethane/60 dichlorotetrafluoroethane).

EXAMPLE 8

A radiation shielding agent in aerosol form with the following composition:

A mixture of 2.0 g hydrogenated, ethoxylated (10 mol) lanolin, 7.0 g triglyceride of caprylic-caprylic acid, 0.7 g cetyl alcohol, 0.7 g stearyl alcohol, 5.0 g paraffin oil, 2.5 g ethylhexyl- p-Methoxycinnamate and 3.0 g of stearic acid were melted at 70°C. After addition of 2.0 g of micronized guanine, 0.8 g of netanolamine in 75.1 g of demineralized water was added at 70°C with stirring to the resulting suspension. The mixture was stirred for 15 minutes and then cooled. 0.2 g of perfume and 1.0 g of rectified alcohol were added at 45°C. The resulting mixture was stirred until cold and an emulsion with a viscosity of 550 cp. was achieved. 88 parts by weight of this emulsion were mixed in an aerosol container with 7.2 parts by weight of dichlorodifluoromethane and 4.8 parts by weight of dichlorotetrafluoroethane.

EXAMPLE 9

A radiation shielding agent in milk form with the following composition:

A mixture of 1.8 g hydrogenated, ethoxylated (10 mol) lanolin, 7.0 g triglyceride of fatty acid from coconut, 0.6 g cetyl alcohol, 0.6 g stearyl alcohol, 5.0 g paraffin oil, 2.5 g ethylhexyl- p-Methoxycinnamate and 3.0 g of stearic acid were melted at 70°C. After addition of 2.0 g of micronized guanine, 2.0 g of carboxyvinyl polymer in 72.2 g of demineralized water was added at 70°C with stirring to the resulting suspension. The mixture was stirred for 15 minutes and then cooled. 0.8 g of triethanolamine and 0.5 g of perfume were added at 50°C and 45°C respectively. The resulting mixture was stirred until cold and snow white milk was stable at 3,000 rpm. minute for 1 hour was achieved. Viscosity: 6000 cp. (Broockfield, Spindle 4.10 revolutions per minute).

Claims (1)

Protective agent against ultraviolet radiation, characterized in that it contains, as active compounds, cytosine, uracil, guanine and/or 5-chloro-uracil in a total concentration of active compounds of 1 - 30%, preferably 2 - 5%, and possibly an additional common light protective agent .