Guanidine derivatives and process for their production

Details Guanidine derivatives and process for their production Guanidine derivatives and process for their production

1997-11-06

2001-02-13

O'Sullivan, Peter (Department: 1621)

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

Organic compounds

Amino nitrogen containing

C560S055000, C560S106000, C560S110000, C560S251000, C564S232000, C564S237000

Reexamination Certificate

active

06187955

ABSTRACT:

BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to cosmetics which have a keratin layer softening effect and which provide a good feeling when used, to guanidine derivatives including acid addition salts thereof which have a moisturizing effect, a keratin softening effect, etc. and are useful as components of cosmetic formulations and to a process for the production thereof.
2. Discussion of the Background
The keratin layer, the outermost layer of the skin, becomes dry and rough during exposure to low temperature, low moisture, etc., conditions (e.g., in the winter season) or when contacted with detergents or solvents in excess amounts. It is thought that such changes in the skin occur when a hygroscopic water soluble component, called NMF (natural moisturizing factor), in the keratin layer is lost causing a reduction in the water content of and in the softness of the keratin layer. As a consequence, conventional cosmetics for use in softening the skin are blended with various types of moisturizing agents including natural moisturizing components such as organic acids and amino acids, for the purpose of providing the keratin layer with a large quantity of moisture for a prolonged period of time.
An example of such skin softening cosmetics are those in which an &agr;-hydroxy acid having a keratin layer softening function is blended as an organic acid as in JP-A-55-19291 (the term “JP-A” as used herein means an “unexamined published Japanese patent application”). However, &agr;-hydroxy acids have a disadvantage in that their effects are transient and can be obtained only within a low pH range (pH 2 to 4) which inhibits normal skin physiology.
In order to resolve such a problem, some cosmetics are adjusted to a neutral pH range by supplementing them with strong alkalis such as sodium hydroxide, potassium hydroxide and the like or amines such as triethanolamine and the like. These strong alkalis, however have a disadvantage in that the quality of the resulting cosmetics cannot be maintained at a constant level, because these alkalis spoil the stability of the cosmetics when blended in a large amount, and it is difficult to accommodate the pH range of the skin. Amines, on the other hand, are not desirable from a safety point of view because of the possibility to cause allergic reaction.
In order to resolve such problems caused by the blending of &agr;-hydroxy acids, cosmetics in which &agr;-hydroxy acids are used in combination with basic amino acids have been proposed for example in JP-B-3-30556 (the term “JP-B” as used herein means an “examined Japanese patent publication”), but their skin softening effects are not sufficient.
In addition, cosmetics blended with amino acids and their derivatives have been proposed with the aim of obtaining skin softening through improvement of the moisturizing effect, such as those in which the hydrolysate of coix seed and the like are blended (for example, JP-B-58-8007) and in which various types of peptides are blended (for example, JP-A-48-23944, JP-A-62-99315 and JP-A-2-178207). The skin softening effect of these amino acids and peptide compositions, however, are not sufficient.
OBJECTS OF THE INVENTION
An object of the present invention is to overcome the aforementioned problems involved in the prior art and provide skin cosmetics which can soften the keratin layer without spoiling its normal skin physiology and give a proper feeling when used.
SUMMARY OF THE INVENTION
In view of the above, the present inventors have discovered that the use of a guanidine derivative having a specified structure and acid-addition salts thereof provide cosmetics having excellent keratin layer softening effects which are superior to conventional materials in which basic amino acids are used alone or in combination with dicarboxylic acids. The present invention has been accomplished on the basis of this finding.
Thus, according to the present invention, there is provided a guanidine derivative represented by formula (1), (2) or (3)
wherein A and B may be the same or different from each other and each represents an alkylene group having 2 to 8 carbon atoms, D represents a single bond, —CO— or an alkylene group having 1 to 6 carbon atoms which may have a substituent group, E represents a hydrogen atom, a lower alkyl group, an aralkyl group or an aryl group which may have a substituent group, m is an integer of 1 to 6, n is an integer of 0 to 6 and R
1
represents a hydrogen atom, a lower alkyl group or —(AO)
m
—(BO)
n
—D—E, with the provisos that —(AO)
m
—(BO)
n
—D—E is not a hydroxyethyl group when R
1
is a methyl group, that R
1
is not hydrogen when A is a straight chain alkylene group, m=1 and n=0, that —(AO)
m
—(BO)
n
—D—E is not hydroxyethyl when R
1
is hydrogen, a methyl group or a hydroxyethyl group and that —(AO)
m
—(BO)
n
—D—E is not a lower alkoxyethyl group when R
1
is hydrogen, in formula (2), 1 is an integer of 1 to 10, G represents a hydrogen atom, a hydroxyl group, a carboxyl group, a sulfonic acid group or a phosphoric acid group and R
1
is as defined immediately above, and, in formula (3), one of R
2
, R
3
and R
4
is a hydroxyl group and others are hydrogen atoms. Acid addition salts of Formula (1), (2) or (3) and a process for the production of compounds of Formula (1), (2) or (3) are also part of the invention.
DETAILED DESCRIPTION OF THE INVENTION
The invention guanidine derivative and an acid addition salts thereof are compounds represented by the aforementioned formula (1), (2) or (3). In the formula (1), the alkylene group having 2 to 8 carbon atoms represented by A and B may be either a straight-chain or a branched-chain group, which include ethylene, trimethylene, tetramethylene, pentamethylene, hexamethylene, propylene and like groups, of which those having 2 to 6 carbon atoms are preferred, more preferred are those having 2 to 4 carbon atoms such as ethylene, trimethylene and propylene groups.
The alkylene group having 1 to 6 carbon atoms represented by D may be either a straight-chain or a branched-chain group, which include methylene, ethylene, trimethylene, tetramethylene, pentamethylene, hexamethylene, propylene and like groups.
Examples of the lower alkyl group represented by E or R
1
include straight- or branched-chain alkyl groups having 1 to 5 carbon atoms, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, tert-butyl, pentyl and like groups, of which methyl is particularly preferred.
Examples of the aralkyl group represented by E include those which have 7 to 12 carbon atoms, such as benzyl, phenetyl, naphthylmethyl and like groups.
Examples of the aryl group represented by E include phenyl, naphthyl and like groups, and their substituent groups include amino which may be substituted with a methyl or like lower alkyl group; nitro; cyano; hydroxyl; a carboxylic acid residue which may form an ester with a lower alkyl group, a lower alkyl halide or an aralkyl group; carbamoyl; a halogen atom such as fluorine, chlorine, bromine, iodine or the like; a lower alkyl group such as methyl, ethyl, propyl, isopropyl or the like; and a lower alkoxy group such as methoxy, ethoxy or the like.
In formulae (1), (2) and (3), m is an integer of 1 to 6, preferably 1 to 4, and n is an integer of 0 to 6, preferably 0 to 4.
In the formula (2), R
1
is as defined above, 1 is an integer of 1 to 10, preferably 1 to 5, and G is preferably a hydroxyl group, a carboxyl group or a phosphoric group.
In formula (3), a compound wherein R
3
is a hydroxyl group, R
2
and R
4
are hydrogen atoms is particularly preferred. Steroisomers are existed in compounds represented by formula (3) by an asymmetric carbon atom. These steroisomers are also included in the present invention.
Illustrative examples of guanidine derivatives represented by formula (1), (2) or (3) include 2-hydroxyguanidine, 3-hydroxyguanidine, 2-hydroxypropylguanidine, 4-hydroxybutylguanidine, 5-hydroxypentylguanidine, 6-hydroxyhexylguanidine, 2-(2-hydroxyethoxy)ethylguanidine, 2-[2-(2-hydroxyethoxy)ethoxy]ethylguanidine, 1

Affiliated with

Also associated with

Rating

Guanidine derivatives and process for their production does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Guanidine derivatives and process for their production, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Guanidine derivatives and process for their production will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2565830