Primary amine salts derived from amino acids containing a uretha

Details Primary amine salts derived from amino acids containing a uretha Primary amine salts derived from amino acids containing a uretha

1994-08-15

1999-09-28

Shippen, Michael L.

Organic compounds -- part of the class 532-570 series

Organic compounds

Carboxylic acid esters

514 47, 514 59, 514 63, 514 7022, C07C26100

Patent

active

059591374

DESCRIPTION:

BRIEF SUMMARY
The invention relates to new primary amine salts of urethanes derived from amino acids, and to their use, in particular, as emulsifying and hydrating agents in cosmetic compositions.
In Patent Application FR 89/09328 (Publication No. 2,649,697), urethanes derived from certain amino acids or from the salts of the said acids have been described as hydrating agents or surfactants in cosmetic or pharmaceutical compositions intended for the treatment of dry skins. In this prior patent application, the preparation of certain salts is described, in particular metal salts, ammonium salts and tertiary amine salts.
However, the use of the urethane derivatives and of their salts described in the prior patent application creates particular formulation problems. These products, in acid form, are very sparingly soluble in water at room temperature. On heating, for example to approximately 80.degree. C., the formation of a substantially homogeneous gel is achieved. However, the acid pH of such a gel does not permit these products to be formulated in compositions for the skin. In addition, on cooling to room temperature, the acid reprecipitates.
When an attempt is made to circumvent this difficulty by salifying using a base such as sodium hydroxide or triethanolamine, the aqueous phase containing the acid has to be heated. When the gel is formed, an aqueous solution of the chosen base is added dropwise, and when stoichiometry is reached, a clear solution of the salt formed is obtained. However, on cooling to room temperature, the formation of a precipitate is observed, during the cooling or after a few days at most.
An effort has thus been made to solubilize the said urethane derivatives, in a mixture of water and oil, by forming an emulsion in the heated state.
With the unsalified derivatives, microscopic observation shows that a very fine emulsion is obtained at 80.degree. C. However, on cooling to room temperature, the texture becomes completely heterogeneous with, in particular, a precipitation of crystals.
The salts of the said urethane derivatives also enable fine emulsions to be obtained. However, with the tertiary amine salts such as the triethanolamine salt, the emulsion separates into two phases after approximately two weeks.
It has, on the other hand, been discovered that, surprisingly, with some of the said urethane derivatives of serine or threonine, salified with a primary amine, it is possible to obtain emulsions that remain stable for several months.
The subject of the invention is hence the primary amine salts of the derivatives of formula (I): optionally unsaturated alkyl group having at least 10 carbon atoms, as well as the at least partial salification products of the derivatives of formula (I) with primary amines, and the degree of salification of which is sufficient to obtain a pH above 6 and below 7.5 in aqueous solution.
Salification products are understood here to mean the compounds obtained by salification of the compounds of formula (I) with a primary amine in proportions which are not necessarily stoichiometric. However, in the present application, the expression "primary amine salts" will denote, except where otherwise stated, both the actual salts and the other salification products, and vice versa.
In particular embodiments, the primary amine salts of the derivatives of formula I which are useable according to the invention can possess the following features, taken separately or, where appropriate, in combination: atoms, and in particular 16 carbon atoms; represent an optionally hydroxylated lower alkyl; R.sub.2 represents, for example, --CH.sub.3 or --CH.sub.2 OH, and R.sub.3 can represent --CH.sub.3, --C.sub.2 H.sub.5 or --CH.sub.2 OH; 2-amino-2-methyl-1-propanoland 2-amino-2-hydroxymethyl-1,3-propanediol; derivatives of formula I can itself be an amino acid containing at least two amino groups, such as, for example, lysine or arginine.
The process for preparing the compounds of formula I and their salts is described in French Patent Application 89/09328 (Publication No. 2,649,697). It wil

REFERENCES:
patent: 4282203 (1981-08-01), Jacquet
patent: 4324780 (1982-04-01), Jascquet
patent: 4595585 (1986-06-01), Papantoniou
patent: 5112601 (1992-05-01), Sebag
patent: 5182407 (1993-01-01), Sebag
patent: 5230890 (1993-07-01), Philippe
patent: 5470579 (1995-11-01), Bonte
Michalun, "Milday's Skin Care and Cosmetic Ingredients Dictionary," pp. 76 & 294 May, 1994.

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