CA2068427A1 - Riboflavin as a tanning enhancer - Google Patents

Abstract

A method of enhancing in vivo melanin production is disclosed. The method comprises topically applying an effective amount of riboflavin, riboflavin phosphate or mixtures thereof to the surface of the skin. Also disclosed is a composition for enhancing in vivo melanin production. The composition comprises an effective amount of riboflavin, riboflavin phosphate or mixtures thereof. The composition can contain at least one other ingredient selected from the group consisting of: Protein Kinase C Activators, DOPA phosphates, sunscreening agents, emollients, emulsifiers, solvents for sunscreening agents, waxes, thickeners, film formers, humectants, antioxidants, perservatives, surfactants, perfumes, biological additives, buffering agents, chelating agents, emulsion stabilizers, opacifying agents, pH adjusters, propellants and coloring agents. The Protein Kinase C Activators in the methods and compositions of this invention can be selected from the group consisting of: diacylglycerols, triacylglycerols, lipopolysaccharides, unsaturated free fatty acids, short chain saturated free fatty acids, glycerolphospholipids, enzymes which hydrolyze glycophospholipids to diacylglycerols, and bryostatins.

Description

~0 91/n716~ 9()/(~632~;
20~27 .R!~QFI ~VI~ -?~

~EF,EREMC~ TQ ~1. T~n A~~ TI.~M
This application is related ~o ;,,y ~Y~n~ y~ i n ~ ri No. 07/434,0~7 filed November 9, 1989, tne disciosure ol wnich 1S
incorporated herein by reference thereto.

This invention relates to the enhancement of melanin production by the topical application to the skin of Riboflavin.

BACKGROUND
Melanin pigmentation is largely responsible for normal skin color and protection against ultraviolet damage, including photocarcinogenesis. Melanin is produced in melanocytes, neural crest derived cells situated in the basa!
layer of the epidermis, and is transferred via dendrites to surrounding keratinocytes, the most abundant cell in the epidermis~ Gordon et al. disclose that this anatomical relationship, terme~ the epidermal melanin unit, is envisioned as one melanocyte in contact with an estimated 36 keratinocytes in the basal and suprabasal layers. According to Gordon et al., the rates of pigment synthesis and transfer by melanocytes appear to be influenced by ultraviolet light exposure and by certain inflammatory processes, but the precise factors regulating human epidermal pigmentation are unknown. Gordon et al. also disclose that it is also unknown whether these stimuli act directly on melanocytes, keratinocytes, other cells that in turn WO 91/n~16~ -r/~ ~;9n/()632~;

release m~lanccyte rneaialors or vi~ ~oth direct and indirect mechanisrns. ~cenr~ns i~o Go,~n et e~ the c~ose physical cont~c~ "e ep!à~rma' melanin unit make keratinocyte mediation of melanocyte 5 function 2in ?~r~ic~ e h~ ot~ . S~e ~-CrC~.Cn. D,~,, et al.
"Reguiatio.n of ~lui~an ,`vlelanocyte Growth. Der,dricity, and Melani~ C`~tiQ ~ C~ . Journal of I n v e s t i n .q~ t ! ~ ? ~ r~ a ~ o ~
1 0 obse, \,/c~r~ " ,~ viC~i' r~d,a~io l~ are phOtcoxicoa~io" evon;), aeiayed sunbu"n, and ;anning. Josnl e; al.
disclose that a wide variety of short-lived reactive oxygen species are known to be generated in skin photosensitization 15 reactions in the presence of exogenous or endogenous photosensitizers such as riboflavin. Joshi et al. disclose an in vitrQ study of the role of reactive oxygen in photosensitization and tanning reaction using riboflavin (RF), hematoporphyrin (HP), 3-carbethoxypsoralen (3-CP), and 8-methoxypsoralen (8-MOP).
20 Joshi et al. report that reactive oxygen produced by photosensitized RF, ~-CP. and 8-MOP w~as found to oxidize tyrosine and DOPA to dopachrome and subse~uently their conversion to melanin. ~)oshi et al. also report that DOPA was oxidized to dopachrome and subse~.uently to melanin at a variable 25 rate RF>3-CP>HP>8-MOP. According to Joshi et al., their observations appear to have relevance to the oxygen-requiring immediate tanning reaction of the skin stimulated by the UVA
(320-400 NM) portion of solar radiation and in the induction of skin photosensitization. See Joshi. P.C. et al., "Involvement of 30 Reactive Oxygen SDecies in the Oxidation of Tvrosine and DOPA to Melanin and In Skin Tanning," Biochemical and Biophysical Research Communications~ Vo!~ 142. No. 1, P? 265-274, January 1~, 1987.
Those skilled in the art will recognize that there is 35 no data presented in the in vitro study of Joshi et al. that '0 91/()716~ ~'1`/~ /n~32X

-3- 20~8427 supports the authors inference that tne in VitrQ
photosensitization of tyrosine and DOPA to dopachrome also resulted in the subsequent conversion of do~ ci,r^"ie ~o r"e,.
It will be appreciated by those skilled in the art that the in 5 vitro study of Joshi et al. relates to imrnediaie ,annin~ (iT) reactions, also known as immediate pigment darkenin~ (IPD) IPC
is a transient phenomenon observed in tne s~in a,t~, ir r aàia~ion that then fades away Immediate ~anning. m,cty beg,r, i,~,media~ ;y and fade within seconds to a minute or may ~ers,sl ~!j;" hiohe doses or longer exposures for 1~2 to 1 hour o u? t~, 24 hcurs Rarely, IT may persist for 36-48 hours a'te p, o!o~g.Qc ev ~osurc at which s;age it blenàs with deiayed ;annlng ~ e~ ~egan editor, The Science of Photomedicine, pp. 241-2~2, 1982.
According to Fitzpatrick et al., IT occurs within minutes of 15 exposure to UVA (320-400 nm) and to visible light Fitzpatrick et al. disciose that IT becomes most prominent within 1 hour of exposure and almost completely disappears within 4 hours.
Fitzpatrick et al. further disclose that studies with electron spin resonance have shown that IT reaction is probably an oxidation 20 reaction that involves the generation of unstable semi-quinone-like ~ree radicals in melanin. According to Fitzpatrick e~ al. DT
develops 48-72 hours after exposure to UV light, and DT involves new production of melanosomes and therefore appears slowly over a period of days. See Fitzpatrick et ai., editors, Sunlight 25 and Man, p. 17~, 1974. Thus, there is no disclosure nor suggestion relating to the in vivo effects of, for example, riboflavin on melanogenesis (tanning).
It is also known that the key steps in the biochemical pathway of melanogenesis are the hydroxylation of tyrosine to 30 dopa (3,4-dihydroxyphenylalanine) and the oxidation of dopa to dopaquinone via the catalytic action of the enzyme tyrosinase.
Duggan et al. disclose that the reactions beyond dopaquinone (see for example their Fig. 2 on page 9, in the reference cited at the end of this paragraph) were once believed to be spontaneous but 35 that it has been determined that these reactions are regulated by WO 91/()71~X ~ 9n/n632~;
~0~2r~

several biological fac~ors. Accordi,lc ~o Du~g~n at âl., dopachrome conversion fac~or ~Ci-) incre~ses the conversion Of dopach ro m a -~o ~ J~ ! i7~ ox y ~ v i~
conversion factor (ICF) increases the conversion of ~,6-5 dihydrox~inn'o!~ ~o ~h ~ r.~ m~ ni ~.
According to Duggan et al, the ~esire for a ciee?~ dar!~ tan has generated the ,orclifer~.tii~n ~ c~ c~ c!~imins to Monteii's P-r~ l an ~ ;e! ~: ``_` i `, _ `; ,'~ `_;:`!.`- _` .` ~':~!iC~~~
10 Accelerator with ~ i~io-, ;~n ~ frp!ex ~ nc i~icugh'~
Coppertone l~llaturai lan Accelera~or ( ~ v) L~uigcian et a'. tur~ne~
ciisclose that these products contain tvrosine. tvrosine derivatives, tyrosine/riboflavin complex andior amino acid blends. According to Duggan et al., tyrosine is used to increase 15 the substrate available for tyrosinase, and tyrosine was complexed with riboflavin in order to accelerate tyrosine's oxidation. See Duggan, M., et al., ~Tyrosinase...The Enzyme Behind the Tan", Cosmetics ~ Toiletries, pp. 97-101, March 1987.
Consumers are becoming more and more health 20 conscious, and as such there is increasing concem over excessive exposure to soiar or artificially produced UV radiation àuring attempts to obtain a tanner appearance. The production of melanin is the body's response to exposure to UV radiation which results in a tanned appearance. A method and a composition for 25 enhancing or increasing melanin production upon exposure to UV
radiation which can result in a faster, darker and safer tan and would be a welcome contribution to the art. This invention provides just such a contribution.

SUMMAR`' ~F TU' I~IV'~IT!O~!
It has surprisingly and unexpectedly been discovered that topical applications of effective amounts of riboflavin as the only active ingredient --i.e.~ nct complexed ~rith other substances such as tyrosine-- are ;,ufficient!y absorbed through 35 the skin to effect an enhanced, po;entiated or increased WO 91/n716X l'(-r/~'S9n/~)~32X

-5- 2~8~27 production of melanin upon exposure of the s~in .o UV, abiati^n.
This is particularly surprising, because in vitro effects o riboflavin on melanin precursors is not sugges~ cl ~
enhancement of melanogenesis by riboflavin, particularly wne 5 such in vjyo use is by topical applications to the ~'~ir,. Thu~
has been discovered that an effective amount of ribofiavin~ when applied to the skin, penetrates the stratum corn~um anG ti~e epidermis to ~e~ch the melanocytes. Withou~ h~,n~, ~^ `oa `~o~n_' by theory, it is believed that ~he absorbed ribo~
10 potentiates or increases the growth and repiication of melclni"
precursors (such as tyrosinase, melanosomai ?roiei~ an~
melanoprotein) upon exposure to UV radiation (UVA 320-400 nm and/or UVB 290-320 nm) through interaction with the cell membrane and/or nuclear membranes. This enhanced production 15 of melanin precursors, enzymes and ultimately melanin itself results in more melanin being produced than would normally be produced under similar conditions but without the topical use of effective amounts of riboflavin.
Thus, this invention provides a method of enhancing 20 melanin production comprising applying topically to the skin an effective amount of a vitamin selected from the group consisting of riboflavin, riboflavin phosphate and mixtures thereof. The riboflavin, riboflavin phosphate or mixtures thereof is applied in amounts effective to stimulate the enhanced production of 2~ melanin. Generally, the riboflavin, riboflavin phosphate or mixtures thereof is combined with suitable solvents and other optional ingredients and applied as a composition.
Another embodiment of this invention provides a topical composition for enhancing melanin production comprising 30 an affective amount of riboflavin, riboflavin phosphate or mixtures thereof. The topical composition may optionally contain effective amounts of protein kinase C (PK-C) activators, - DOPA phosphates and/or sunscreening agents.
Yet another embodiment of this invention provides a composition comprising: .

WO 91/n716~ P(~T'/~'~9~ 632~i ~0~8~27 (a) riboflavin, ribofla~ir, ohos?h~ e or mixtllr~â ~h~r~c~
effective to enhance "me'an", ~rGuuc~ioll when saià composition is ~ooi~ ~o~io~,iv to ~ile skin, and (b) a p~ysi~ic~ ?~
mixture comorising ~v;.~ ;n(~ e;,eO;~ ?
amount of a hu~ecta"

Stiil ailo.h~ D~Jvi~ f`; ~ ;vi~
provides a composition comprising:

(a) riboflavin, riboflavin phosphate or mixtur`es thereof present in an amount effective to enhance melanin production when said composition is applied topically to the skin, (~) a physiologically acceota~le cosolvent mixture comprising water and an effective amount of a humectant, and (c) optionally, at least one ingreàient selected from the group consisting of: PK-C activators, DOPA
phosphates, sunscreening agents, emollients, emulsifiers, solvents for sunscreening agents, solvents for said PK-C activators, waxes, thickeners, film formers, antioxidants, preservatives, surfactants, perfumes, biological additives, buffering agents, chelating agents, emulsion stabilizers, opacifying agPnts, pH adjusters, propellants, and coloring agents.

wo 91/n716~3 PC-r/-;~Ci9()/~)fi32X
7 20~8~27 Preferably, when PK-C Activators are added tc the compositions, an antioxidant is used.

DETAILED DESCRIPTION OF THE INVENTION
In general the riboflavin, riboflavin phosphate or mixtures thereof are in a concentration which is effecti~e to provide the desired levei of activity. Usually the riboflavin~
riboflavin phosphate or mixtures thereof are present in ~n amoui,t of at least about 0.0~ percer,; by weight of .i1e e~a~
composi~ion~ Generally, the riboflavin, riboflavin phosphate or mixtures thereof are present in an amount of about 0.1o ;O a~o 2% by weight of the total composition with about O.l~o to abou~
0.3% being preferred and about 0.15% to about 0.3% being most preferred and about 0.2% to about 0.3% being even more 1 5 preferred.
Generally, the composition is applied in a sufficient amount to uniformly coat the skin. Usually the composition is applied in an amount sufficient to provide about 0.01 mg to about 0.08 mg riboflavin, riboflavin phosphate or mixture thereof to an area Ot skin about 10 to about 12 cm2, with about 0.01 mg to about 0.06 mg riboflavin, riboflavin phosphate or mixture thereof being preferred and about 0.02 mg to about 0.0~ mg being most preferred. Normally, the riboflavin, riboflavin phosphate or mixture thereof composition is applied at least 1 to about 6 times with about 1 to about 3 times being preferred over a time period of about 24 hours.
Conveniently, the riboflavin, riboflavin phosphate or mixtures thereof may be combined with (such as by mixing, blending or dissolving) a known formulation (vehicle) for a sunscreening agent. The inclusion of the sunscreening agent would be optional. Normally, such a formulation contains effective amounts of water and humectant.
The compositions of this invention may also be formed by combining the riboflavin, riboflavin phosphate or mixtures thereof with effective amounts of water and a WO 91/n716f~ i9~ )632X

humectant. These comvositiorns ar~ p.. ed^,A.inant!~ ater ~ ith enough humectant added to ~o~ ^^ co~olve.- ,., x~ul^ .hat wi!
dissolve the riboflavin, , i~o"~i;n ~ a~s~ . s ~ne.
Usually, in these compositions the humectant is present in 5 amounts of about 1 to about '~O b~ .~.ei~ e~ ? \0'^:' composition with about 4 to about 5~i being rreferred. The balance of the comoositiorl is ~'a`~?, SUI^i` `~ "e ;0;~ rn^~.-of ingredients t~.Y~te~, hu"meet~ ~t ~ ^f^~;
phosphate or mixiui_ ~here~ sl 10 compositions may conLain W~iel in àn.Oùll~; 0~ Où~ '`;. ;v acou;
9&.95/o by weight Ot ~he io~ai col-"_oii~iol~ lin GVOU; ;J`I iO
about 98~9~o being suitable. Inese com~osilions may conveniently contain one or more cf the above mentioned opiional ingredients. Thus, the compositionâ with the optional 15 ingredients can contain water in an amount of about 40 to about 86% by weight of the total composition, a humectant in amounts of about 1 to about 7% by weight of the total composition with about 4 to about 5% being preferred, with the balance of ingredients being selected from amongst the optional ingredients 20 such that the total amount of ingredients (components) equals 100% by weight. The co`mposition may be formulated by combining all the ingredients excep; for enough water (e.g., 5~O by weight of the total composition) to make a slurry of the riboflavin, riboflavin phosphate or rnixtures thereof, then tne 25 slurry is added into the composition.
Humectants well known in the art may be used Examples of humectants include propylene glycol, sorbitol, and glycerin. Other suitable humectants may include fructose, glucose, glutamic acid, honey, maltitol, methyl gluceth-10, 30 methyl gluceth-20, sodium lactate, sucrose, and the like.
Liposomes (lipid vesicles) may also prove useful to encapsulate the riboflavin, ribofla~Y,n phosphate or mixtures thereof. Liposomes are aqueous compartments enclosed by a lipid bilayer. They are produced by techniques ~ell kno~n to 35 those skilled in the art. For examp!e, liposomes can be produced ~0 91/1)716X ~ ;9n/()~32~

9 `;'` 20~8~27 by suspending a suitable lipid, such as phosphatidyl choline, in an aaueous medium This mixture is then sonicated to give a dispersion of closed vesicles that are quite uniform in size. See, for example, Stryer, BLgGhem~, Third Edition, pp. 290-292, 5 ~19~8, the disclosure of which is incorporated herein by reference thereto Among the useful liposomes are stratum corneum lipid liposo nes formed from epidermal ceramides, choiesterol palmitic aci~ and cholesterol sulfate as described in A~raham e 10 al~ The Journal of Investigative Dermatology, ~Q, 259-262 (1 9~8~.
-lany lipids are believed suitable for use in making the liposom-~s, many of which are commercially available, e.g Liposome ~ t is available from Sigma Chemical Company, St.
1~ Louis, Missouri under catalog number L-4262. Liposome Kit L-4262 contains L-alpha-phosphatidylcholine (egg yolk), dicetyl phosphate and cholesterol. It is a negatively charged lipsome mixture, another suitable negatively charged liposome mixture available from Sigma Chemcial Company is L-4012 which 20 contains L-alpha-phosphatidylcholine, dicetyl phosphate and cholesterol Suitable positively charged iiposome mixtures available from Sigma Chemical Company contains L-alpha-phosphatidylcholine, stearylamine and cholesterol (catalog numbers L-4, "7 and L-3887).
2~ Categories of lipids in suitable liposomes are phospholipids, glycosphingolipids, ceramides, cholesterol sulfate anà neutral lipids. Various combinations of these lipids are found in neonatal mouse, pig and human stratum granulosum and stratum corneum. Other categories of lipids which can be 30 used to make the liposomes are straight chain fatty acids, glycerol esters, glycerides, phosphoglycerides, sphingolipids, waxes, terpenes and steroids. Specific preferred lipids suitable for use are phosphatidyl choline, dicetyl phosphate and cholesterol .

WO 91 /n7 1 hX T'C~ i9()/()f~32~i The riboflavin, riboflavin ~hos~ ;u,~
thereof can be encapsulated in (or ,rapped in, ~ c~ e,~, portion of the liposome by addi"~
riboflavin phosphate or mixtures thereof and cosolvent mixture 5 to a suitable lipid and mixing (--e.~,., s~n`ic^.~;n ,` ~, .~r~ c? '.`.~.-liposomes containing the riboflavin~ riDoflavin Dhcs~hat~ or mixtures thereof.
T h ~ l i p o s c m e c ~ n ~h topical ~ehicle~ e~g. a lo.ion, ~,~i o The lipid mixture whicl1 ,o,~ ;"~ O!'l~ cai~
any of ,he conventional mixtures avaii~oi ~ o,- ui~ Jà~ " ~, le literature which are pharmaceutically and cosmeticallv acceptable .
Preferred lipid mixtures contain a phosphatidyl 15 choline, dicetyl phosphate and cholesterol~ The lipid mixtures which form the liposomes are commercially available in a solvent such as ethanol or chloroform. A typical mixture contains on a weight basis, seven parts phosphatidylcholine, 2 parts dicetyl phosphate and one part cholesterol The compositions of this invention can contain a penetration enhancer to enhance the absorption of the ri~o,lavin, riboflavin phosphate or mixtures thereof into the skin. The enhancer can be used in amounts of about 0.5% to about 99% by weight of the total composition, with abou 1i~ to about 25%
being preferred and about 2% to about tO~o being most prefarred.
Representative examples of penetration enhancers include, but are not iimited to: DMSO (dimethyl sulfoxide), Azone (laurocapram, 1-dodecylazacycloheptan-2-one, from Nelson Research, Irving, CA), N-methylpyrrolidone, alcohols such as panthenol, the SD alcohols and ole,^ alcohol, fatty acids such as oleic acid and linoleic acid, liposomes, and the like.
The compositions of this invention can contain, as stated above, PK-C activators, DOPA phosphates (such as a mixture of monophosphorylated isomers of DOPA --.see IJ.S.
Patent No. 4.508,706, the disclosure of whicn is incorporated WO 91/n716~ PC'1/~:~9n/(~632~;
20~8~27 herein by reference thereto) sunscreening agents, emollients, emulsifiers, solvents for sunscreening agents, waxes, ~hic!<eners, film formers, humectants, antioxidants, preservatives, surfactants, perfumes, biological additives, 5 buffering aaents, chelating agents, emulsion stabilizers, opacifying agents, pH adjusters, propellants, coloring agents~ and the like. The compositions ca~ be formed into formulations, such as lotionc, creams, gels, aero~31s, and sticks~ in accordance w~th, proc~dur~ Ye'l ~nown in the ar~.
The PK-C Activator i usefu! in this invention are those Activators which are ph~siologically com~atible with t~,~
skin, are readily absorbable thr~ ugh or into the skin, and penetrate through the stratum t orneum and the epidermis to reach the melanocytes The P~-C Activators may be used 15 individually or in combination. Suitable PK-C Activators are those physiologically acceptable substances which activate protein kinase C by their d~!ect action, or are substances which are metabolized to other substances which activate protein kinase C, or are substances which act upon other substances to 20 produce a resulitng substance that activates protein kinase C
and may include substances selected from the group consisting of: diacylglycerols; triacylglycerols; lipopolysaccharides;
unsaturated free fatty acids; short chain saturated free fatty acids; glycophospholipids; enzyr,~es which hydrolyze 25 glycophospholipids (phosphoglycerides) to diacylglycerols such as Phospholipase C which hydrolyzes the phosphodiester bond linking the phosphorylated inositoi unit to the acylated glycerol moiety to form diacylglycerol in the phosphoinositide cascade;
and naturally occurring substances such as bryostatins which 30 are naturally occurring macrocylic lactones found in bryozoa.
The acyl groups.of the diacylglycerols and triacylgiycerols can be unsaturated, saturated or a combination of unsaturated and saturated. Each acyl chain (group) contains at least 1 ca!bon atom (including the carbonyl carbon) and usually 35 contains from about 1 to about.30 carbon atoms (including the wo 91/n71hX ~ )6?~
20~8~27 carbonyl carbon) with about 2 to about 24 carbon atcms being preferred and about 6 to about 20 carbon atcms being mos~
preferred. Normally, the acyl group is deriv~d ,rom a n~.~.,a,l~
occurring fatty acid and the fatty acid usual!y contains ~ e~Jer number of carbon atoms and is unbranched ,~itnou~ 2-di~cy rac-glycerols are useful, the diacylglycerols are.~ r~
diacylglycerols! and most preferai~lv 1,2-d,iac~ ce Representative saturated tree fa~ty IC,i~ ,a;~
acids) from ~hich the acyl groups may ~e ~
but are not limited to: methanoic (formic); ethanoic (aceticj propanoic (Dropionic); butanoic (buty!ic~: c~ent-neic ~ c' hexanoic (caproic); heptanoic (enanthic); OC'~nv'C (~ n,"~'`);
nonanoic.(pelargonic); decanoic (capric); undecanoic (undecylic) dodecanoic (lauric); tridecanoic (tridecylic); tetradecanoic (myristic); pentadecanoic (pentadecylic); hexadecanoic (palmitic); heptadecanoic (margaric); octadecanoic (stearic);
nonadecanoic (nonadecylic); eicosanoic (arachidic);
heneicosanoic; docosanoic (behenic); tricosanoic; tetracosanoic;
pentacosanoic; hexacosanoic (cerotic); heptacosanoic;
octacosanoic (montanic); nonacosanoic; triacontanoic (melissic);
and the like. Preferred saturated acyl groups are derived from fatty acids selected from the group consisting of: acetic, hexanoic, octanoic, decanoic, hexadecanoic. octadecanoic, and eicosanoic. Most preferred saturated fatty acids are selected from the group consisting of: acetic, hexanoic, octanoic and octadecanoic Representative unsaturated free fatty acids (fatty acids) from which the acyl groups may be derived from include, but are not limited to:
l. 10-undecenoic (lO-undecylenic);
2. cis-9-tetradecenoic (myristoleic);

3 cis-9-hexadecenoic (palmitoleic);

4. trans-9-hexadecenoic (palmitelaidic);

5. cis-6-octadecenoic (petroselinic);

6. trans-6-octadecenoic (petroselaidic);

wo 9l/n7l6~ PC'r/-'Ci9~ )632X

- 13- 2068L~27 7. cis-9-octadecenoic (oleic);

8. trans-9-octadecenoic (elaidic);

9. cis-~ 1-octadecenoic (cis-vaccenic);

10. trans-11 -octadecenoic (trans-vaccenic);

11. cis-12-hydroxy-9-octadecenoic (ricinoleic);

12. trans-12-hydroxy-9-octadecenoic (ricinelaidic);

13. cis-9,12-octadecadienoic (linol~ic);
1~. trans-9,12-octadecadienoic (linulelâidic);
I6. cis-6,~,12-octaàecatrienoic ~g-linoienic);
16. cis-9,12,15-octadecatrienoic (lir olenic);
17. cis-6,9,12,15-octacecatetraenoic:
18. cis-11 -eicosenoic (gondoic);
19~ cis-13-eicosenoic;
20. cis-11,14-eicosadienoic;
15 . 21. cis-8,11,14-eicosatrienoic;
22. cis-11,14,17-eicosatrienoic;
23. cis-5,8,11,14-eicosatetraenoi_ (arachidonic);
24. cis-5,8,11,14,17-eicosapentaenoic;
25 cis-13-docosenic (erucic);
26~ trans-13-docosenoic (brassidic);
27 cis-13,16-docosadienoic;
28~ cis- 13,16,19-docosatrienoic;
29. cis-7,10,13,16-docosatrienoic;
30. cis-4,7,t 0,13,16,19-docosahexanG.-;
2~ 31. cis-15-tetracosenoic (nervonic); and the like.

Preferred unsaturated fatty acids are selected from the group consisting of: cis-9-octadecenoic; and cis-5,8,11,14-eicosatetraenoic Representative diacylglycerols include, but are not limited to:
1 diarachidin (dieicosanoyl-glycerol, reported to be approximately 50% 1,3- and 50% 1,2-isomer);
2. 1,3-diarachidin (1,3-dieicosanoylglycerol);

WO 91/1)716X PCl'l-'X9(~/()fi3~

20~8427 14-3 dicaprin (didecanoylglycerol repo"ed .o ~e 50% 1,3- and 50% 1,2-isomer);
4. 1,3-dicaprin (1,3-diàecanoyiglyce,o,3, 5. dicaproin (dihexanoylglycerol~ reported to be 5 50~O 1,3- and ~0% 1,2-isomers);
6 dicapryiin (1,3-dioctanoylglvcerol);
7. 1,2-didecanoyl-rac-glycerol (, 2-~ic 8 1,3-di cis-11-eicose,no,n;
9. 1,3-dielaidi.n (1,3-ci-~(trar,~
l 0 octadecenoyl]glycerol);
lO 1,3-dierucin (1,3-ài-l~cis) 13 aocosenoY ;-rac-giycerol);
11. 1,2-dihexanoyl-sn-glycerol;
12. dilaurin (didodecanoylglycerol, reported to be approximately 50% 1,3- and 50% 1,2-isomer);
13. 1,3-dilaurin (1,3-didodecanoylglycerol);

14. 1,2-dilauroyl-rac-glycerol (1,2-didodecanoyl-rac-glycerol);

15. dilinolein (1,3-di-[(cis.cis)-9,12-octàdecadienoyl)-rac-glycerol);

16 dilinoleni`n (di-[(cis,cis~cis)-9,12,1~-octadecatrienoyl]g lycerol);

17. dimyristin (ditetradecanoylglycerol, reported to be approximately 50% 1,3- and 50% 1,2-isomer);

18. 1,3-dimyristin (1,3-ditetradecanoylglycerol);

19. 1,2-dirnyristoyl-rac-glycerol (lt2-ditetradecanoyl-rac-glycerol);

20. 1,2-dioctanoyl-rac-glycerol (1,2-dicapryloyl-rac-glycerol);

21. 1,2-dioctanoyl-sn-glycerol (1,2-dicapryloyl-sn-glycerol);

22. diolein (di-[(cis)-9-octadecenoyl]glycerol.
reported to be approximately 85% 1,3- and 15% 1,2-isomer);

23. 1,3-diolein (1,3-di-[(cis)-9-octadecenoyl);

WO 91/n716X PC'r/~'S9~/06325;
20~8~27 24. 1,2-dioleoyl-rac-glycerol (1,2-di[(cis)-9-octadecenoyl]-rac-glycerol);
~ 5. 1,2-dioleoyl-sn-glycerol t1,2-di[(cis)-9-octadecenoyl]-sn-glycerol);
26 dipalmitin (dihexadecanoylglycerol, reported to be approximately 50% 1,2- and 50% 1,3-isomer);
27~ 1,3-dipalmitin (1,3-dihexadecanoylglycerol);
,3-dipalmitolein (1,3-di-~cis)-9-f!~gly~,-r~');
29. 1,2-dipalmitoyl-sn-glycercl ~1~2-dihe~âàe~,ânoy'-sn-glycerol);
30. 1 ,2-dipalmitoyi-rac-glycerol ( 1 ,2-dihexadecanoyl-rac-glycerol);
31. 1,3-dipentadecanoin (1,3-15 dipentadecanoylglycerol);
32. distearin (dioctadecanoylglycerol. reported tobe approximately 50% 1,3- and 50% 1,2-isomer);
33. 1,3-distearin (1,3-dioctadecanoylglycerol);
34. 1,2-distearoyl-rac-glycerol (1,2-20 dioctadecznoyl-rac-glycerol);
35. 1-oleoyl-2-acetyl-rac-glycerol (1-[(cis)-9-octadecenoyl]-2-acètyl-rac-glycerol);
36. 1 -oleoyl-2-acetyl-sn-glycerol ( 1 -[(cis)-9-octadecenoyl)-2-acetyl-sn-glycerol);
2~ 37. 1-palmitoyl-3-stearoyl-rac-glycerol ~1-hexadecanoyl-3-octadecanoyl-rac-glycerol);
38. l-stearoyl-2-arachidonoyl-sn-glycerol (1-octadecanoyl-2-[(cis,cis,cis,cis)-5,8,1 l ,14-eicosatetraenoyl]-sn-glycerol);
39. 1-acetyl-2-oleoy'glycerol (1-ethanoyl-2-[(cis)-9- octadecenoylglycerol);
40. 1-stearoyl-2-oleoylglycerol (1-octadecanoyl-2-[(cis)-9-octadecenoylglycerol; and the like.

WO 91/1)~ 9n/~)fi32X
2 0 ~ 8 ~ 2 rl Preferably the diacylglycerol is selected from the group consisting of:
1~ 1,2-dihexanoyl-sn-glycerol;
2. 1,2-dioctanoyl-rac-glycerol;
3. 1,2-dioctanoyl-sn-glycerol;
4 . 1 -o le oyl-2-acetyl - rac-g Iyce ro l;
. 1-oleoyl-2-ac~tyl-sn-glycerol;
6. 1-stearoyl-2-arachidonoyl-sn-glyc~rol:
7 1,2-didecanoyl-rac-glycerol~
8 1-acetyl-2-oleoyl glycerol;
a l-stearoyl-2-oleoyl glycerol;
10. "2-dipalmitoyi-rac-glycerol;
11. 1,2-dipalmitoyl-sn-glycerol;
12~ 1,2-distearoyl-rac-glycerol;
13. 1,2-dioleoyl-rac-glycerol;
14. 1,2-dioleoyl-sn-glycerol;
15. diarachidin;
16. 1,3-diarachidin;
17. diolein;
18. 1,3-diolein;
19. dipalmitin;
20. 1,3-dipalmitin;
21. distearin; and 19. 1,3-distearin.
Most preferably the diacylglycerol is selected from the group consisting of:` 1,2-dihexanoyl-sn`-glycerol; 1,2-dioctanoyl-rac-glycerol; 1,2-dioctanoyl-sn-glycerol; 1-oleoyl-2-acetyl-rac-glycerol; 1-oleoyl-2-acetyl-sn-glycerol, or 1-30 stearoyl-2-arachidonoyl-sn-glycerol Most preferably 1,2-dioctanoyl-rac-glycerol or 1,2-dioctanoyl-sn-glycerol is used.
Diacylglycerols are available commercially from, for example: (1) Sigma Chemical Company, St. Louis, MO. --see Sigma's 1989 catalogue of Biochemicals Organic Compounds for 35 Research and Diagnostic Reagents; (2) Serdary Research '0 91 /n7 I hX ~'C-r/~ ~;9(~ 632~;
^ 206g~27 Labor~t^ri~s~ Port Huron, Ml; (3) Molecular Probes Inc., Junction City, O~; and (4) Avanti Polar Lipids, Birmingham, AL.
~ i_cylsycarols may also be prepared in accordance with proc~dures well known in the art, for example see: (1) 5 Gunstcn~ at a!.~ editors, The LjQd~Qh PP. 295, et seq.~
~3t986; (2) Ebeling et al., Proc. Natl. Acad. Sci. USA, Vol. 82, pp 815-~,9~ oage 81c~ February 1985; and (3) Ganong et al., Proc ~\la~ c~r.. ~ci. US.~, Vol. ~3, ~o. 1184-1188, March 1986.

i~e?resentati~e triacylglycerols may include b~ are no. Ii",i.c~
1. 1,2-dilauroyl-3-myristoyl-rac-glycerol (1,2-didodencanoyl-3-tetradecanoyl-rac-glycerol);
2. 1 ,2-dimyristoyl-3-lauroyl-rac-glycerol ( 1,2-15 ditetradecanoyl-3-dodecanoyl-rac-glycerol);
3~ 1,2-dimyristoyl-3-oleoyl-rac-glycerol (1,2-ditetradecanoyl-3-[(cis)-9-octadecenoyl]-rac-glycerol);
4 1,2-dimyristoyl-3-palmitoyl-rac-glycerol (ditetradecanoyl-3-hexadecanoyl-rac-glycerol);
205. 1,2-dioleoyl-3-palmitoyl-rac-glycerol (1,2-di-[(cis3-9-octadecenoyl]-3-hexadecanoyl-rac-glycerol);
6. 1,3-dioleoyl-2-palmitoylglycerol (1,3-di-~(cis)-9-octadecenoyl]-2-hexadecanoylglycerol);
7. 1,2-dioleoyl-3-(pyren-1-yl)decanoyl-rac-2~glycerol);
8~ 1,2-dioleoyl-3-stearoyl-rac-glycerol (1,2-di-[(cis~-9-octadecenoyl~-3-octadecanoyl-rac-glycerol);
9 1,3-dioleoyl-2-stearoylglycerol (1,3-di-[(cis)-9-octadecenoyl]-2-octadecanoylglycerol;
3010. 1,2-dipalmitoyl-3-myristoyl rac-glycerol (1 ,2-dihexadecanoyl-3-tetradecanoyl-rac-glycerol);
11. 1,2-dipalmitoyl-3-oleoyl-rac-glycerol (1,2-dihexadecanoyl-3-[(cis)-9-octadecenoyl]-rac-glycerol);
1~. 1,3-dipalmitoyl-2-oleoylglycerol (1,3-35dihexadecanoyl-2[(cis)-9-octadecenoyl]glycerol);

WO 91/()716~ 'T'/~'~91)/~h32X

2~6842~ - 18-13. 1,2-distearoyl-3-myristoyl-rac-glycerol (1,2-dioctadecanoyl-3-tetradecanoyl-rac-glycerol);
1~. 1,2-distearoyl-3-oleoyl-rac^glycerol (1~2-dioctadecanoyl-3-[(cis)-9-octadecenoyl]-rac-glycerol);
515. 1,3-distearoyl-2-oleoylglycerol (t,3-octadecanoyl-2-[(cis)-9-octadecanoyl]glycerol);
16. 1,2-distearoyl-3-palmitoyl-rac-glycerol (1,2-dioctadecanoyl-3-hexadecanoyl-rac-glycerol);
17 1-~almitoyl-2-oleovl-3-stearovl-rac-alycero 10 (1-hexadecanoyl-2-[(cis)-9-octadecenoyl]-3-octaaecanoyl-rac-glycerol~ ~
18. triacetin (1,2,3-ttiacetyiglyce,o'; gi~ceryi triacetate);
19. triarachidin (1,2,3-trieicosanoylglycerol);
20. triarachidonin (1,2,3-tri-[(cis,cis,cis,cis)-5,8,1 1 ,14-eicosatetraenoyl]glycerol);
21. tribehenin (1,2,3-tridocosanoylglycerol);
22. tributyrin (1,2,3-tributyrylglycerol; glyceryl tributyrate);
23. tricaprin (1,2,3-tridecanoylglycerol);
24. tricaproin (1,2,3-trihexanoylglycerol;
trihexanoin);

25. tricaprylin (1,2,3-trioctanoylglycerol; glyceryl tricaprylate);

26. tri-1 1-eicosenoin (1 ,2,3-tri-[(cis)-11-eicosenoyl]-glycerol);

27. trielaidin (1,2,3-tri-[(trans)-9-octadecenoyl]glycerol);

28. trierucin (1,2,3-tri-[(cis)-13-30 docosenoyl]glycerol);

29. triheptadecanoin (1,2,3-triheptadecanoylglycerol);

30. trilaurin (1,2,3-.ridodecanoylglycerol);

31. trilinolelaidin (1,2,3-tri-[(trans,trans)-9,12-35 octadecadienoyl]glycerol);

WO 91 /n7 1 hX PC'r/ - ~9()/()632X
2~68427 ~2. trilinolein (1,2,3-tri [(cis,cis)-9,12^
octadecaàienoyl]glycerol);
~ ,~. ,rilinolenin (1,2,3-tri-[(cis,cis,cis)-9,12,15-octadecatrienoyi]-glycerol);
~ trirnyfistin. (1,2,3-tritetr~decanoylglycerol);
35. trimyristolein (1~2,3-tri-[(cis)-9-tetr~Qr~ .ly~r~
u~. .r,"e,voi,in ~ 3-.ri^~(cis)-15-3 . trinonadecanoin ~ 1 ,2,3-trinonaaecanoyiaiyc2~ ol) ' ~ 8 trinonanoin (1~2,3-trinonanoylglycerol;
pelargonin);
39 triolein (1,2,3-tri-[(cis)-9-15 octadecenoyl]glycerol; glyceryl trioleate);
40. tripalmitin (1,2,3-trihexadecanoylglycerol);
41. tripalmitolein (1,2,3-tri-[(cis)-9-hexadecenoyl~-g Iycerol);
42. tripentadecanoin (1,2,3-20 tripentadscanoylglycerol);
43 tripetroselinin (1~2,3-tri-~(cis)-6-octadecenoyl~-glycerol);
44. tristearin (1,2,3-trioctadecanoylglycerol);
45. tritridecanoin (1,2,3-tritridecanoylglycerol);
and the like. These triacylglycerols are commercially available from Sigma Chemical Company (same address and catalogue as cited above). Triacylglycerols may also be prepared in accordance with procedures well known in the art, for example 30 see Gunstcn~ et al., editors, The Lip`~ Handbook, p. 295 et seq., ~1 986.
Lipopolysaccharides (LPS! may also be useful in this invention as PK-C Activators. The active lipid moiety of LPS of Gram-negative bacteria is diacylgluccsamine 1-phosphate. Thus, 35 either a diacylglucosamine 1-phosphate or the LPS containing it WO 91/n716X PC~ 9~ 632X

206~2 ~ -20-may be used The acyl groups of the diacylglucosamine 1-phosphates from LPS are usually from predominantly C14 to C18 fatty acids w,1ich may be saturated or monosaturated, but not polyunsaturated On LPS and bacterial fatty acids see, for 5 exam"!e, ~avis et al., editors, Microbiology, Third 'dition, pp 82 to 9t~ ~1980~ the disclosure of which is incorporated herein by reference thereto.
R~p,esenta.i~e examples of bacteria ',om ~hich LPS
can be de,~ d ~rom tor use in this invention incluae~ but are no-~10 limitec to: Escherichia coli (E. coli)~ Klebsiella pneumoniae~
Pseuaomonas aeruginosa~ Salmonelia abortus equi, Salmonelia enteritiàis. Salmonella minnesota~ Salmonella typhimurium, Salmonella typhosa, Serratia marcescens, Shigella flexneri, Vibrio cholerae, and the like. Bacterial Lipid A and Lipid X may 15 also prove useful. Lipid A and Lipid X are well known to those skilled in the art. See for example: (1) Wightman et al., The Journal of Biologic~L Chemistry, Vol. 259, No. 16, pp 10048-10052, August 25, 1984; and (2) Davis et al., editors, Mi~robiology, Third Edition, pp. 85, 87, and 654-655, ~1980; the 20 disclosures of each being incorporated herein by reference thereto. Lipid A is commèrcially available from, for example, Sigma Chemical Company. Lipid X is available from Lipidex, Inc., Middleton, Wl.
LPS are available commercially, for example, form 2~ Sigma Chemicai Co. (already cited aboYe). Examples of LPS
available comercially inc!ude those derived from: E. coli Serotype 026:B6; E~ coli Serotype 055:B5; E. coli Serotype 0111:B4; E. coli Serotype 0127:B8; E. coli Serotype 0128:B12; E.
coli EH-100 (Ra mutant); E. coli F-583 (Rd mutant); E. coli Strain 30 J5 (Rc mutant); E. coli K235, Klebsiella pneumonia;, Pseudomonas aeruginosa; Pseudomonas aeruginosa Serotype 10 (Habs);
Salmonella abortus equi, Salmonella enteritidis, Salmonella Minnesota, Salmonella Minnesota Strain R5; Salmonella Minnesota Strain R7 (Rd mutant); Salmonella Minnesota Strain Re 3~ 595 (Re mutant); Salmonella typhimurium; Salmonella W0 91/n71hX l~r/~ss~/()632x 20~8~27 typhimurium Strain TV119 (Ra mutant); Salmonella typhimurium Strain SLS~ (Rc mutant); Salmonella typhimurium Strain SL11 3-t, (I~e ~u.~ ); Salrncnellâ 'yphoâa~ Serratia marcescens;
Shigella ~le~neri Sero~ype lA; Shigella flexneri (Re mutant); and 5 Vibrio choierae ~erotype INAaA 569B
I ?S may be derived trom bacteria by techniques well kn~ n ~c ~hC~`Q s~cill~d in the art~ Fcr e~ample~ Iyophili~ed po-~def;~ are ~vaiia~le as phenoi~ trichloroacetic acid (TCA), but~n~ p~Qno~ or~l~orm-petrole~ ether extracts Such 10 pro,:edu, es a-~ r efer~nced in Sigma Chemical Company's 1 98a Bio~hem~ca'~ s Corl~pourlds caAalogue (cited above) a~:
Westpnai e; a,."~,ielno~s in ~arDonyarate Cnem~, i, 83 (1965) for a p~enol extraction procedure; Staub, Methods in Carbohydrate Ch~.m~, 5, 92 (1965) for a TCA extraction procedure; Lieve et al., 15 Me,nods in Enzymology, XXVlllb, 254 (1972) for a butanol extraction procedure; and Galanos et al., Eur. J. Biochem., 9, 245 (1969) for a phenol-chloroform-petroleum ether extraction.
Unsaturated free fatty acids (fatty acids) may also be useful in this invention as PK-C Activators. It is believed 20 that unsaturated f.ee fatty acids having 1 to about 4 double bonds and about 14 to about 20 carbon atoms are preferred PK-C
Activators. Cis- and trans-unsaturated free fatty acids are suitable with the proviso that trans-elaidic acid may not be as usefu! as other unsaturated free fatty acids. Although chain 25 lengths of 14-20 carbon atoms are preferred other chain lengths (less than 14 or more than 20) may also prove useful. Suitable unsaturated free fatty acids may be selected from amongst those unsaturated fatty acids already described above for the acyl groups of the diacylglycerols and triacylglycerols.
30 Preferred unsaturated free fatty acids include linoleic acid, arachidonic acid and oleic acid.
Short chain saturated free fatty acids (fatty acids) may also prove useful. Suitable saturated free fatty acids may be selected from, amongst those saturated fatty acids, having 4 35 to 10 carbon atoms, described above for the acyl groups of the wo gl /n, l ~ Cr/1~91~/()632~;

20Ç~8 d~27 - 22 -diacylglycerols and the triacylglycerols~ Saturated fatty acids having more than 10 carbon atoms --e.g., 11-20-- may also prOvQ ;'aef.l ! Thus~ lauric, myristic, palmitic, stearic, and arachidic may be suitable~
,~nother group of compounds which may be use~ul in this invention as PK-C Activators for enhancing melanin produc~cn _rQ slycero?hospholipids (phosphoglycerides)~
Phos!~hogl~cerides consist Ot a glycerol backaround~ two acyl arollps i~r~\!Qd frcm ;atty aci~s (~sually bound to the C 1 ~nd C-2 gl~lcercl ca,bons) and a phosphorylated alcohol~ The major phospl,o..~,.c~lldQs a~e derivativQs cl phosphatida~e àiacyi~lycQrol 3-phospnate)~ Tne phosphate group nf phosphatidate becomes esterified to the hydroxyl group of one of several alcohols~ Examples of alcohols include serire, threonine, 15 ethanolamine, choline, glycerol, inositol, and the like. The disclosure above pertaining to the acyl groups of the di- and triacylglycerols pertain equally as well to the acyl groups of the phosphoglycerides.
Representative examples of phosphoglycerides 20 include, but are not limited to:
1. L-a-phosphatidylcholine (L-a-lecithin) such as that obtained from bovine brain, bovine heart, bovine liver, egg yolk (diced, fresh, frozen or fresh frozen), turkey egg yolk (fresh), and soybean;
2~ 2. L-a-phosphatidylcholine, ,B-acetyl-y-O-alkyl (1 -O-alkyl-2-acetyl-sn-glyceryl-J-phosphorylcholine);
3. D-a-phosphatidylcholine, ~-acetyl-y-O-hexadecyl;
4. DL-a-phosphatidylcholine, ,B-acetyl-y-O-30 hexadecyl;
5. L-a-phosphatidylcholine, ~-acetyl-y- O-hexadecyl;
a-phosphatidylcholine, ~-acetyl-y- O-(octadec-9-cis-enyl);

WO 9l/n7l6x P~ 'C.9n/()632 -23- 20t~8~27 ~ . I-a-phosphatidylcholine, ~-O-acetyl-v-O-octad ecy l;
L-a-ph~sp"atidylcno~,ne~ cety!-y-oieoy! (1-[(cis)-9-octadecenoyl]-2-acetyl-sn-glycero-3-phosphocholine);
9 L-(x-phosphatidylcholine, B-arachidonoyl~ v-stearoyl (l-octadecanoyl-2-i(cis.cis,cis~cis)-~.8.11,1~-eicosatetraer,oyll-sn-~h/ce, 0-3-3hos?hQcnoli"e);
1(~ L-~x- ~ospha~i.dylcilo~ne, d`-- achidoyl;

12 L-a-~ hosphatidylc.noline~ dib~ty.oyl;
.~,. L-c~ ,os?,la~,dy'c"ol;"e~ Gic;,~royl;
1~ L-a-p losphatidylcholine, didecanoyl;
15. L-~-mlosphatidylcholine, dielaidoyl;
16 L-c~ hosphatidylcholine, diheptadecanoyl;
1.~ t7. L-a-i,~hosphatidylcholine, diheptanoyl;
18. DL-c~-phosphatidylcholine, di-O-hexadecyl (1,2-di-O-hexadecyl-rc ~-glycero-3-phosphocholine);
19. DL-a-phosphatidylcholine, dilauroyl (1,2-didodecanoyl-rac-glycero-3-phosphocholine);
20. L-a-phosphatidylcholine, dilauroyl;
21. L-a-phosphatidylcholine, dilinoleoyl;
22. L-a-phosphatidycholine, dimyristoyl;
23. L-a-phosphatidylcholine, dinonanoyl (1,2-dinonanoyl-sn-glycero-~.-phosphocholine);
24. L-~-phosphatidylcholine, dioctanoyl (1,2-dioctanoyl-sn-glycero-3-phosphocholine);
2.~. DL-u-phosphatidylcholine, dioleoyl;
26. L-a-phosphatidylcholine, dioleoyl;
27. D-ct-phosphatidylcholine, dipalmitoyl (2,3-dihexadecanoyl-sn-glycero-1-phosphocholine);`
28. DL-a-phosphatidylcholine, dipalmitoyl;
29. L-a-phosphatidylcholine, dipalmitoyl;
30. L-a-phosphatidylcholine, dipentadecanoyl (1,2-dipentadecanoyl-sn-glycero-3-phosphochoiine);
31. L-a-phosphatidylcholine, distearoyl;

WO 91/n71~X I'CT/-'~i9~ 632~i 2~ 42 - 24 -32. L-a-Dnosphatidylcholine~ diundecanoyl (1.2-diundecanoyl-sn-glycQro-3-phosphocholine);
~ ,^. '_-a~ os~hatidylcholinQ, divaleroyl.
3~. L-a-phosphatidylchoiine, ~-elaidoyl-y-5 palmitoy,;

33~ L-a-phosphatidylcholine, ~-linoleoyl-y-pa~ ito~
3~ DL-a-ohosohatidylcholine~ ~-O-methyl-y-O-hex~t~Qcy ~-O-i~v?~eQcyl-~ -nnQthy!-rac-9lycQro-3 ,ohospi~oc"oiine`;
3. L-~ nosp,nat,àylcholinQ~ ,~-O-methyl-~-C-octa~ ecy i;
3~ L-a-pnosphatidylcholine, ,B-(NBD-aminohexanoyl)-~-palmitoyl (1-h~xadecanoyl-1-[(N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)-aminohexanoyl]-sn-glycero-3-phosphocholine);
39. DL--phosphatidylcholine, ,B-oleoyl-y-O-hexadecyl (1-O-hexadecyl-2-[(cis)-9-octadecenoyl]-rac-glycero-3-phosphocholine);
40. L-a-phosphatidylcholine, ~-oleoyl-y-palmitoyl;
41. L-a-phosphatidylcholine, ,B-oleoyl-y-stearoyl;
42. DL-a-phosphatidylcholine, ,B-palmitoyi-y-O-hexadecyl (1-O-hexadecyl-2-hexadecanoyl-rac-glycero-3-phosphocholine);
2~ 43. L-a-phosphatidylcholine, ,B-palmitoyl-y-oleoyl;
44. L-a-phosphatidylcholine, ~-palmitoyl-y-(pyren-1 -yl)-hexanoyl;
4~. L-a-phosphatidylcholine, ,B-(pyren-1-yl)decanoyl-~-palmitoyl;
46. L-a-phosphatidylcholine, ,B-(pyren-1-yl)hexanoyl-y-palmitoyl;
47. L--phosphatidylcholine, ~-stearoyl-y-oleoyl;
48. DL-a-phosphatidyl-N,N-dimethylethanolamine, dipalmitoyl;

WO 91/~)716X PC~ 9~ 632X

' '' 2~g8~227 49. L-~-phosphatidyl-N,N-dimethylethano,amine, dipalmitoyl;
~ 0. L-~ oap~ iyle~ia;l3~a~ (L-~-c~?~a!lrl)~
such as that obtained from bovine brain, sheeD brain, egg yolk, 5 soybean, ~scherichia coli, coy ~rain, ho\~ine !i~.~e!, or, orcine liver;
51 L-a-phosphatiàylQ~`han~ ir~ diheptadecanov!
(t,2-dih~ptadecanoyl~sn-g,y~e,c,-3~ ci ;r;~e_~,.li-iO'al..i.i~
~ 2. L-a-~ilosulldi~ ;;";,.~ ~i..l~,~,Vi \ ..2-10 ' didoaecanoyl-sn-giycero-3-phos?hoeti~i~,.oiam re~;
53. L--pnosuhali~yie,nan ~lamine. ~imyri~i~oyi (1,2-ditetradecanoyl-sn-glycero-3-ohos~ noetnanolamine);
54. phosphatidylethanolarT ne, dinitrophenyl;
55. L--phosphatidylethan. Iamine, dioleoyl (1,2-15 di[(cis)-9-octa-decenoyl~-sn-glycero-3-!~hosphoethanolamine);
56. DL-o~-phosphatidylethanolamine, dipalmitoyl;
~7. L-a-phosphatidyle'.lanolamine, dipalmitoyl;
58. L-a-phosphatidylethanolamine, dipalmitoyl-N-dansyl (1,2-dihexadecanoyl-sn-glycero-3-phospho-[N-20 dansyl]ethanolamine);
59. L-a-phosphatidylethanolamine, dipalmitoyl, N-fluorescein isothiocyanyl t1,2-dihexadecanoyl-sn-glycero-3-phospho-[N-fluorescein isothiocyanyl~ethanolamine) sodium salt;
60. L--phosphatidylethanol~ mine, dipalmitoyl, N-2~ NBD (1,2-dihexadecanoyl-sn-g!ycero-3-phospho-[N-(4-nitrobenzo-2-oxa-1 ,3-diazole)]ethanolamine);
61. L-a-phosphatidylethanolamine. distearoyl ~1,2-dioctadecanoyl-sn-glycero-3-phosphoethanolamine);
62. L--phosphatidylethanolamine, ~-linoleoyl-y-30 palmitoyl (1-hexadecanoyl-2-[(cis,cis)-9,1 2.octadecadienoyl]-sn-glycero-3-phosphoethanolamine);
63. L--phosphatidylethanolamine, ~-oleoyl-~-pal mitoyl;
64. phosphatidylethar,olamine, p!asmalogen;
65. phosphatidylethanolamine, N-trinitrophenyl;

WO 9 1 /()7 1 6X pc~ ;9~ )632~

20fi~27 26 -36. L-c~-ohosDhatidyl-DL-glycerol (1-[3-sn-phosphaiid~l]-rac-glycerol) [pre?ared by reaction of cabbage phoslphe ~ h~ ?~;, yoi'c '~ -~v-~hos3hatidylcholine in the presence or giycerol]~ including the ammonium salt from egg yolk 5 lecithin ~rd ~.~ne so~ m salt from e~g yolk lecithin;
~ ,. L-~-phcsphatidyl-DL-glycerol, dimyristoyl (1~2~ e~ -a,-~yi-sn-gh~,ero~3-~phospho-rac-~1-glycerol~]), includ!.ng ~h~ ~m~ r~um a!ld scdi~!m salts;
v ~r~ ?~ L-gl~!cero!~ dioiQoyl (1~2-10 di[(ci~ e:_d~cen^, !,~-~n-ghJcero-3-~phospho-rac-(1-c ~
y y _ ~ V . j J ~
. ~- uL-c~-?nospnati~y!-DL-g~ycerol, dlpaimitoyl (1 ,2-dipalmito~ l-rac-glycero-3-~phospho-rac-(1 -glycerol)]), including the arnmorlium salt;
70. L--phosphatidyl-DL-glycerol, dipalmitoyl (1 ,2-dihexadecanoyl-sn-g!ycero-3-[phospho-rac-(1 -glycerol)]), including the ammonium and sodium salts;
71. L-a-phosphatidyl-DL-glycerol, distearoyl (1,2-distearoyl-sn-glycero-3-lphospho-rac-(1-glycerol)]) ammonium 20 salt;
72. L-c~-phosphatidylinositol, e g from soybean (including tne ammonium ar,d soàium salts). and from bovine liver (ammonium salt), as well as TYPE 1: Folch Fraction 1 from bovine brain reported to contain 10-20% phosphatidyl inositides, 25 50-60% phosphatidyl serine as well as several other brain lipids;
73. L-a-phosphatidyiinositol 4,5-diphosphate (triphosphoinositide) sodium salt from bovine brain;
74. L-c~-phosphatidylinositol 4-monophosphate 30 (diphosphoinositide) sodium salt frorn bovine brain;
75. phosphoinositides, sodium salt, from bovine brain, 'xtract Type 1, reported to contain approximately 15-20%
phosphatidylinositol 4-monophospha;e and phosphatidylinositol 4.5-biphosphate with the remainder being a mixture of 35 phosphatidylinositol and phosphatidylserine;

WO 91/n716X l'CI`/~'~i9n/n632X

-27- 2~8~27 76. L-a-phosphatidyl-N-monometnvlethanoiamine dipalmitoyl;
77. L-a-phosphatidyi~ p~i"l ~c~ e~ /c nc~ ~in,e.
dipalmitoyl (1,2-dihexadecanoyl-sn-glycero-3-phospho-[N-5 hexadecanoyl]ethanolamine) amrnon,um s_lt;
78~ L-a-phosphatidyl-L-serine~ e~g.~ from bovine brain (including the sodium salt), as ~ve'l as TY?'~ o~c,~
Fraction lll from bovine brain re~o~e~ ~o cc"ta~ " 80 phosphatidylserine ~ h the ~)a!anc` ~~`i,.~ ~''l`.s- ~` a 79 L-c~-phosph~tidY!sr-ri!lQ~ d~ns~ nd ~ 30 . D L - - p h o s ~ L- ~ n ~ ! r.' `; 3,: .
In general the PK-C Activator is in a conGen~ratl )n which is effective to provide the desired level of activity. ~` he PK-C Activator may be used in amounts of about 0.01% lo a out t5 20% by weight of the total composition with about 0.05% tc about 10% being preferred and about 0.05% to about 1.0% being most preferred. Combinations of PK-C Activators may t? used such that their total amount is within the specified ranges Suitable solvents for use with the PK-C Activators 20 include liposomes; ketones such as acetone and the like; alcohols such as benzyl alcohol, ethanol, t-~utyl alcoho!, cetyl alcoho!, glycol (HOCH2CH2OH), isopropyl alcohol, propylene glycol, SD
alcohol 23-A, SD alcohol 39-C, SD alcohol 40, SD alcohol 40-B
and the like; Fats and oils such as avocado oil, cocoa butter, 2~ coconut oil, corn oil, hydrogenated coconut oil, hydrogenated cottonseed oil, hydrogenated vegetable oil, lanolin oil, min'~ oil, palm oil, peanut oil, safflower oil, soybean oil, sunflower c eed oil, sweet almond oil, vegetable oil (expressed oil of vegetable origin consisting primarily of triglycerides of fatty acids), 30 wainut oil, wheat germ oil and the like; hydrocarbons such as mineral oil and the like; alkoxylated alcohols or polymeric ethers such as PEG-8, PEG-14M and the like; lanolin and lanolin derivatives such as hydrogenated lanolin and the like; glyceryl esters and derivatives such as hydrogenated palm kernel oil and 3~ the like; esters such as isopropyl myristate, isopropyl palmitate wo 91/n71~X PC~ i9n/~632~`;
2~8i-127 and th~ ';Q; ~iYat~r; and ~he !ike Addition solY~nts which may be used car, ~e ,ou;li~ on i'li~italds, Editoi-, ÇTFA ~QsmAetic ~ redien.
Ha~db~ u'~ , "`~ &i~s.~i~ti~, Toi!et~y an~
Fragrance Association, Inc., 1110 Vermont Avenue, N~W., 5 Washing,,v~ .C., (~ he ;lisclosure of ~,vhich is incorporated herein bv re,erence thereto. In particular~ see the section `'Solv;~r,~ o ~ . Tne disciosu, e a~,ove relating to the enca~ or mi~tures 10 The liposoi"as may alSO ~Ja used as a sol~er,~ fo~ the BK-C
Acti~a.oi~ o~ ay usev ~o ~l~nv Wi~il ;ne B,<-~, Actl~ators âO
that the PK-C Activators are in the liPid layer. The riboflavin, riboflavin phosphate or mixtures thereof may b~ combined with the PK-C Activators and the resultant combination may be 13 encapsulated in liposomes.
Since, in general, PK-C Activators are lipophilic, it rnay be desirable to add components to the water when making up aqueous solutions for encapsulation in liposomes. These added components would be water miscible and would improve the 20 water solubility of the PK-C Activators. These components may include solvents such as alcoho,s ar,d ketones already discussed above.
It is desirable to use compositions containing PK-C
Activators immediately after they arP prepared or to freeze 25 them at about -20C until they are ~sed. If this is not convenient then it is necessary to add an effective amount of at least one antioxidant to protect the PK-C ActiYator from degradation. However, if a PK-C Activator is used which will not degrade over time then an antioxidant is no longer necessary 30 but its use is still preferred. Generally, about 0.05 to about 0.10% by weight of the total composition of an antioxidant is sufficient. Any of the antioxidants known for ùse in the cosmetics industry may be used. Examples of antioxidants include but are not limited to beta-carotene~ BHA, BHT, a-35 tocopherol, propyl gallate, sodium bisulfite, sodium wo 91 /n7 16~; PCI`/ ~ ~9~ )632ti 2~68~27 metabisulfite, ascorbyl dipalmi~ate, TENO~ (trademar'~ ior food grade antioxidants reported to contain one or r"ore of the following ingredients: butylated hydroxyani~o,_, vliiyia~o hydroxytoluene, and/or propyl gallate with or without citric 5 acid; some formulas are supplied in so'vei,ms s~vh as ,ar~pyl~n~
glycol), and the like~ See, for examp~e ~E~eti~ Inn ~ ,,r ~k~ cited above.
If desirable, at least or,~ .Oi,v.. ".a, ~ dd~
the compositions containing riDo.ia~, n~, ri ~ `.!_`. ` l `'``i~"`p.`~
10 mixtures thereof but no PK-C Ast,va~3r. Tno ~,c~...nt oi antioxidant usea would be the s~me as d!scuss~ ove ~or use with the PK-C Activators.
DOPA phosphates can be used in amounts of about 0.005% to about 1.0% by weight of the total composition with 15 about 0.015% to about 0.5% being preferred and about 0.05% to about 0.02% being most preferred.
The DOPA phosphates (phosphodopas) are O-phosphorylated derivatives of DOPA. The DOPA phosphates are represented by Formulas l-V:

H
I

R10~ Ct 12--C CO2R3 ¦ l NH2 (~) wo sl/n7l~x ~cr/- ~9()/()632~

2 0 ~ 7 30 ? ~

r~ ~ i (II~, ~1 ~`i;
Ho o H

(R40) ~ NH2 (R~0)2P--f ~3~CH2_C_Coz:~3 wherein Rl and R2 each represent hydrogen or wo 9l/n7l6~ PC~ ;9~ 632X

_31_ 2~8~27 (R~o~2i'~

R1 and R2 together represent 4 ll/
~ 3--P\

wherein R~ and R3 each represent hyàroaen or a pharmaceutically acceptable cation; with the oroviso that Rl anc R2 cannot both be hydrogen.
The sunscreening agents used can be of the UVA type, UVB type, or a combination of both. Generally, the sunscreening agents are used in amounts effective to provide the desired level of protection against UVA and/or UV~ radiation. Usually, the sunscreening agents are used in amounts of about 2% to about 15 20% by weight of the total composition with about 5% to about 18% being preferred and about 2% to about t5% being most preferred .
Typical UVB type sunscreening agents include substituted para-aminobenzoates, alkyl esters of para-20 methoxycinnamate and certain esters of salicylic acid.
Typical UVA type sunscreening agents include certainbenzophenones and dibenzoyl methanes.
Representative UVB type sunscreening agents include but are not limited to:
~5 (A) DEA Methoxyinnamate (diethanolamine salt of p-methoxy hydro cinnamate), e.g., tradename BERNEL HYDRO from Bernel Chemical Co.. Inc.;

WO 91/11716~ 'S9~ 632X
.
2068~27 - 32 ^

(B~ Eth~JI ~ihydrovypro~yl P.~BA ~ethyl dihydr C`'`f,i~rC~`JI p-.~minoben~vatQ), e.9., "~ ? .~ ol Co~ .;

(C! ~!ycery` .~ Alyceryl-?-^;".~no, Qnzoâte~ e.s., ~radename NIPA G~i\A~P~A fror~, NIPA
Labcl^a,ori ~s 1"c.:

1 0 ~1 ~c~, ~ S I ~ S ~ Y~u~T.I<~
v ~ i C a l;

(E) Octocrylene (2-ethylhexyl-2-cyano-3.3-diphenylacrylate), e.g, tradename UVINUL N-1~ 539 from BASF Chemical Co.;

(F) Octyl Dimethyl PABA (Octyl dimethyl p-aminobenzoate, 2-ethylhexyl p-dimethylaminobenzoate, Padimate O), e.g., - tradenames AMERSCOL, ARLATONE UVB. and ESCALOL 507 from Amerchol Corp., ICI
Americas, Inc, and Van Dyk. respectively;

(G) Octyl ,Methoxycinnamate (2-ethylhexyl-p-methoxycinnamate), e.g.. tradename PARSOL
MCX from Bernel Chemical Co. Inc., or Givaudan Corp.;

(H) Octyl Salicylate (2-ethylhexy salicylate), e.g., tradename SUNAROME WMO from Felton Worldwide, Inc.;

(I) PABA (p-amino benzoic acid). e.g., tradename PABA from EM Industries, Inc. and National WO 9 1 /07 1 6X PCr/ ~ 9(\/(~632X

33 2068~27 Starch & Chemical Corp~, or tradename NIPA
PABA from NIPA Laboratories Inc;

(J) 2-Phenyl-benzimida ole-5-Sulphonic acid (Novantisol), e.g~, tradename EUSOLE~ ~232 ana Ni-O-HELlOPAN HYDRO from EM Industries, Inc and Haarmann & Reimer Çorp~, respecti~/ely;

(K) TEA Salicylate (triethanolam~ne ~?iiCyi?~e) e~g~, tradenames SUNARO~lE W and SUNAROt`.1E B~
from Felton Worldwide~ Inc;

(L) 3-(4-methylbenzlidenejcamphor or 3-(4-methylbenzylidene)boran-2-one, e.g., tradename EUSOLEX 6300 from EM Industries, Inc.; and (M) Etocrylene (2-ethyl-2-cyano-3,3'-diphenylacrylate), e.g., tradename UVINUL N-3 from BASF Chemical Co.
- Representative UVA type sunscreening agents inciude but are not limited to:

(A) Benzophenone-3 (2-hydroxy-4-methoxy-benzophenone), e.g., tradename SPECTRA-SORB
UV-9 and UVINUL M-40 from American Cyanamid Co. and E3ASF Chemical Co., respectively;

(B) Benzophenone-4 (sulisobenzone), e.g., tradename UVINUL MS-40 from BASF Chemical Co.;

WO 91/1)716~ PCr/1:.~9~ 632X

20~8427 (C) Benzophenone-8 (diovybenzon~ .9., tr dename SPECTRA-SOR5 "V-2~ f,o~ ric~n Cyanam,d C~

(D) Menthyl ,~nt'~r2ni'ate '`~ ~nt ~
aminobenzoate), e~ .ra~enam~ SUNA~OI~lE UVA
from Fel~on `~ vi '~ Ino.

1 0 e.~ ~ . trad~r~ S~ ou, om ~A~,; vl~" ,~ vv ~ r,~ ;, ;
Inc~ ~ respectively;

(F) Benzophenone-2 (2,2',4~4'-telrahydroxy-benzohpenone), e.g., tradename UVINUL D-50 from BASF Chemical Co.;

(G) Benzophenone-6 (2,2'-dihydroxy-4,4'-dimethoxy-benzophenone), e.g., tradename UVINUL D-49 from BASF Chemical Co.;

(H) Benzophenone-12 (octabenzone), e.g., tradename UVINOL 408 from BASF Chemical Co.;

( I j 4-isopropyl diben~oyl methane (1 -p-cumenyl-3-phenylpropane-1,3-dione), e.g. tradename EUSOLEX 8020 from EM Industries, Inc.; and (J) Butyl methyl dibenzoyl methane (4-t-butyl-4~-methoxydibenzoyl methane~, e.g. tradename PARSOL 1789 from Givaudan Corporation;

Physical sunscreening agents may also be used. For example, red petrolatum in amounts of about 30 to about 99% by 35 weight of the total composition, or titanium dioxide in amounts WO 91/()~161~ PC'r/~1~9~ )632X
2~8427 ~5 of about 2 to about 25% by weight of the total composition may be used. Talc, kaolin, chalk, and precipitated silica may also be used in ef~ective amounts, e.g., abaut 1% to about 10% by weight of the total composition.
Additional sunscreening agents include lawsone (hydroxynaphthoquinone, C10H6o3t the coloring matter of henna leaves) with dihydroxy acetone.
.Jsually, when used, at leàst one UVB type and at least one U\A type sunscreening agent is used.
For example, at least one of the following UVB type sunscreening agents can be used: from about 1.5 to about 8~0~o by weight of th`' total composition of octyl dimethyl P,~A; ccty!
para- methox cinnamate in amounts of about 1.5 to about 7.5~O
by weight o the total composition; homomenthyl salicylate in amounts of ~ bout 4.0 to about 15% by weight of the total composition; and octyl salicylate in amounts of about 3 to about 5% by weight of the total composition.
Also, for example, at least one of the following UVA
type sunscreening agents can be used: benzophenone-3 in amounts of about 0.5 to at~ut 6% by weight of the total composition; benzophenone-8 in amounts of about 0.5 to about 3% by weight of the total composition; and menthyl anthranilate in amounts of about 3.5 to about 5.0% by weight of the total composition.
Us~rig the ingredients disclosed above (e.g., emollients, emulsifiers, film formers, and the like), the riboflavin, riboflavin phosphate or mixtures thereof can be incorporated into formulations such as lotions, creams, gels mousses, waxed based sticks, aerosols, alcohol sticks and the like. These formulations are well known in the. art, tor example see Balsam, M.S., and Sagrin, E. (Editors) Cosmetic Scie~ç and TechnQlQgy, Second Edition, Volumes 1 and 2, Wiley-lnterscience, a division of John Wiley & Sons, Inc., New York, copyright 1972; and Flick E.W., Cosmetic and Toiletry Formulations, Noyes Publications, 1984.

W0 91/1)716X ~cr/-~s(\/~fi32~

2o68~27 - 36 -Emollients may be used in amounts ;vhic~l ar~
effective to prevent or relie~/e drJnQss. ;Jsef I em^!l ~ms may include: hydrocarbon oils anà `'Ja`''~; :"`1'_'~``'` '` ` :n ` `-`'S' esters; acetoglyceride esters; ethoxyiateà giycerice; alky 5 esters; alkenyl esters; fatty acids; ~a~ a!coh~s~ tt~ ~!c^hc~
ethers; ether-esters; lanolin and deriYativas: polyny~.nc alcoho's (polyols) and polyether derivati~es; '`Ql`jh ;_r`G ~CCnvl ~ ,ol~
esters; wax esters; beeswax deri~a~ es ~ e n;~!? `"?`~
phospholipids; sterols; and arl~
Thus, for example~ ~y~pio^i ~ o:.. en: i.n ~ ine._.
oil, especiali~ minera~ oils ha~:ins ^ ~, is-osi;J i.` ;.~ S
to 500 SUS, lanolin oil, mink oil, coconu. cii, oovva ~ a oiive oil, almond oil, macadamia nut oil, 210e extrac~ jojoba oii, safflower oil, corn oil, liquid lanolin, cotton,eeà oil, peanut oil, 15 purceliin oil, perhydrosqualene (squalene), caster oil, polybutene, odorless mineral spirits, sweet almond oil, avocado oil, calophyllum oil, ricin oil, vitamin E acetate, olive oil, mineral spiri~s, cetearyl alcohol (mixture of fatty alcohols consisting predominantly of cetyl and stearyl alcohols), 20 linolenic alc~hol, oleyl alcoholi octyl dodecanol~ the oil of cereal germs such as the oil Ot wheat germ cetearyl octanoate (~ester of cetearyl alcohol and 2-ethy!hexanoic acid), ce;yl paimitate, diisopropyl adipate, isopropyl palmitate, octyl palmitate, isopropyl myristate, butyi myristate, glyceryl stearate, 2~ hexadecyl stearate, isocetyl stearate, octyl stearate, octylhydroxy stearate, propylene glycol stearate, butyl stearate, decyl oleate, glyceryl oleate, acetyl glycerides, the octanoates and benzoates of (C12-Cts) alcohols, the octanoates and decanoates of alcohols and polyalcohols such as those of glycol 30 and glycerol, and ricin- oleates of alcohols and poly alcohols such as those of isopropyl adipate, hexyl laurate, octyl dodecanoate, dimethicone copolyol, dimethiconol, lanolin, lanolin alcohol, lanolin wax, hydrogenated lanolin, hyaroxylated lanolin, acetylated lanolin, petrolatum, isopropyl lanolate, cetyl 35 myristate, glyceryl myristate, myristyl myristate, myristyl WO 9l/n7l6~ PcT/~i~9n/~632~
20~8~27 lactate, cetyl alcohol, isostearyl alcohol stearyl alcohol, and isocetyl lanolate, and the like~
Emulsifiers (emulsifying agents) may be used in amounts effective to provide uniform blending of ingredients of 5 the composition. Useful emulsifiers may include A~ Anionics 1~ Fatty acid soaps, e.g~, potassium stearate, sodium stearate, ammonium s:earate, and triethanolamine ste~r te;
2 Polyol fatty lcid monoesters containing falty acia soaps, e~g~, glycsrol mono ;learate containins either potassium or sodium salt;
3~ Sulfuric ester (sodium salts), e g., sodium lauryl sulfate, and sodium cet~: sulfate; and 4~ Polyol fatty ~cid monoesters containing sulfuric esters, e.g., glyceryl monostearate containing sodium lauryl sulfate;
B Cationics 1. N(stearoyl colamino formylmethyl) pyridium 20 chloride;
2~ N-soya~ -ethyl morpholinium ethosulfate;
3 Alkyl dimethyl benzvl ammonium chloride;
4~ diisobutylphenoxytheoxyethyl dimethyl benzyl ammonium chloride; and 2~ ~. cetyl pyridium chloride;
C~ Nonionics t. polyoxyethylene fatty alcohol ethers, e.g., polyoxyethylene lauryl alcohol;
2. polyoxypropylene fatty alcohol ethers, e g., 30 propoxylated oleyl alcohol;
3 polyoxyethylene fatty acid esters, e.g, polyoxyethylene stearate;
4 polyoxyethylene sorbitan fatty acid esters, e g, polyoxyethylene sorbitan monostearate;

WO 91/n716~ 9~ )632X

20~8~2 ~ - 38 -5. sorbitan fatty acid esters, e.9., sor3i~an monostearate;
6. polyoxyethyiene glyco' ~a~" -~polyoxyethylene glycol monostearate;
7~ polyol fatty acid esters, e.m~ c eryl monostearate and propylene glycol monostearate; an~
8 ethoxylated lanolin derivatives~ e ethoxylated lanolins, ethoxylated lanol,n ~!co'~
ethoxylated cholostsrol.
Surfactants may also ~e used n ~ne _c,~ ;i_n~ c this invention. Suitable sur,ac~ants may inc~ . e ~"ose ~,_ne, cs"r groupeà as cleansing agents, emulsifying agents, foam bcosters, hydrotropes, solubilizing agents, suspending agents and nonsurfactants (facilitates the dispersion of solids in liquids).
1~ The surfactants are usually classified as amphoteric, anionic, cationic and nonionic surfactants.
Amphoteric surf~ctants include acylamino acids and derivatives and N-alkylamino acids.
Anionic surfactants include: acylamino acids and salts, such as, acylglutamates, acylpeptides, acylsarcosinates, and acyltaurates; carboxylic acids and salts, such as, alkc.noic acids, ester carboxylic acids, and ether carboxylic acids;
sulfonic acids and salts, such as, acyl isethionates, alkylaryl sulfonates, alkyl sulfonates, and sulfosuccinates; sulfuric acid esters, such as, alkyl ether sulfates and alkyl sulfates.
Cationic surfactants include: alkylamines, alkyl imidazolines, ethoxylated amines, and quaternaries (such as, alkylbenzyldimethylammonium salts, alkyl betaines, heterocyclic ammonium salts, and tetra alkylammonium salts).
Nonionic surfactants include: alcohols, such as primary alcohols containing 8 to 18 carbon atoms; alkanolamides such as alkanolamine derived amides and ethoxylated amides;
amine oxides; esters such as ethoxylated carboxylic acids, ethoxylated glycerides, glycol esters and derivatives, monoglycerides, polyglyceryl esters, polyhydric alcohol esters WO 9l/n7l6x Pc~ ssn/0632x ` 2Q68~27 - 39 - ~ .

and ethers, sorbitan/sorbitol esters, and triesters of phosphoric acid; and ethers such as ethoxylated alcohols, ethoxylated lanolin, ~h~xylated polysiloxanes, and propoxylated polyoxyethylene ethers.
Useful solvents for sunscreening agents include those solvents already disclosed as being useful solvents for the PK-C ,~c~ivators .
~uitable waxes which may prove usefu include:
an""~a! .;a~ such as beeswax, s~ermaceti, or wo~l wa~;
tO ~lanolin); ~,.a"t waxes, such as carnauba or candeilla; mineral waxes! sùch as montan wax or 020kerite; and petro ~um waxes, such as paraffin wax and microcrystalline wax (a ~`gh molecular weight petroleum wax). Animal, plant, and some rr neral waxes are primarily esters of a high molècular weight fc ty alcohol with a high molecular weight fatty acid. For exam lle, the hexadecanoic acid ester of tricontanol is commonly reported to be a major component of beeswax.
Suitable waxes which may be useful also include the -synthetic waxes including polyethylene polyoxyethylene and hydrocarbon waxes derived from carbon monoxide and hydrogen (~ischer-Tropsch synthesis).
Representative waxes also include: ceresin; cetyl esters; hydrogenated jojoba oil; hydrogenated jojoba wax;
hydrogenated rice bran wax; Japan wax; jojoba butt r; jojoba oil;
iojoba wax; munk wax; montan acid wax; ouricury wax; rice bran wax; shellac wax; sufurized jojoba oil; synthetic l~eeswax;
synthetic jojoba oils; trihydroxystearin; cetyl alcohol; stearyl alcohol; cocoa butter; fatty acids of lanolin; mono-, di- and triglycerides which are solid at 25C, e.g., glyceyl tribehenate (a triester of behenic acid and glycerine) and C18-C36 acid triglyceride ~a mixture of triesters of C1g-C36 carboxylic acids and glycerine) available from Croda, Inc., New York, NY under the tradenames Syncrowax HRC and Syncrowax HGL-C, respectively;
fatty esters which are solid at 25C; silicone waxes such as methyloctadecaneoxypolysiloxane and poly (dimethylsiloxy) WO 91/()716X rC'r/~9n/~)632X

2~3~27 stearoxysiloxane; stearyl mono- and diethanolamide; rosin and its derivatives such as the abietates of glycol and glycerol;
hydrogenated oils solid at 25C; and sucroglyc~rides.
Thickeners (viscosity control agents) which may be used in effective amounts in aqueous systems include: al~,i";
carbomers such as carbomer 934, 934P, 940 and 9~; cellulose gum; cetearyl alcohol, cocamide DEA, dextrin; gelat r,;
hydroxyethylcelluiose; hydroxypropylceiiuiose; hyc~roxypi~)py, methylcellulose; magnesium aluminum silicate; myri~.yl 10 alcohol; oat flour; oleamide DEA; oleyl alcoho1; PEG 7~1; P_G-14M; PEG-9OM; stearamide DEA; Stearami~e MEA: stearvl alcoho!:
tragacanth gum; wheat starch; xanthan gum; and the like~
In the above list of thickeners, DEA is diethanclamine, and MEA is monoethanolamine Thickeners (viscosity control agents) which may be used in effective amounts in nonaqueous systems include, aluminum stearates; beeswax; candelilla wax; carnauba; ceresin;
cetearyl alcohol; cetyl alcohol; cholesterol; hydrated silica;
hydrogenated castor oil; hydrogenated cottonseed oil;
20 hydrogenated soybean oil; hydrogenated tallow glyceride;
hydrogenated vegetable oil; hydroxypropyl c~llulose; !anolin alcohol; myristyl alcohol; octyldodecyl stearoyl sulfate; oleyl alcohol; ozokerite; microcystalline wax; paraffin;
pentaerythrityl tetraoctanoate; polyacrylamide; polybutene;
2~ polyèthylene; propylene glycol dicaprylate; propylene glycol dipelargonate; stearalkonium hectorite; stearyl alcohol; stearyl stearate; synthetic beeswax; trihydroxystearin; trilinolein;
ttistearin; zinc stearate; and the like.
Suitable film formers which may be used include:
30 acrylamide/sodium acrylate copolymer; ammonium acrylates copolymer; Balsam Peru; cellulose gum; ethylene/maleic anhydride copolymer; hydroxyèthylcellulose;
hydroxypropylcellulose; polyacrylamids; polyethylene; polyvinyl alcohol; pvm/MA copolymer (polyvinyl methylether/ maleic 35 anhydride); PVP (polyvinylpyrrolidone); maleic anhydride WO 9l/n7l6~ Pcr/~sn/~fi32~;
2~68427 -41- . :

copolymer such as PA-18 available from Gulf Science and Technology; PVP/hexadecene copolymer such as Ganex V-216 availabk? 'rom GA' Corporation; acrylic/acrylate copolyme.; and the like~
Generally, film formers can be used in amounts of about 0~1% to about ~0% by weight of the total composition with abou~ o about 8/o ~eing preferred and about 01% to about ~%
being ~1~0Sl o~eferred rfeser\J~tives which may be used in effective amoum~ i,.c!ude: butylparaben; ethylparaben; imida201idinyl urea; ~ ylp~rabel;; O-phenylph~no'; propylpar~er,;
quate,nium-li; qua,ernium-1~; sodium dehyàroacetate; zinc pyrithione; and the like.
The preservatives are used in amounts effective to prevent or retard microbial growth. Generally, the preservatives are used in amounts of about 0.1% to about 1% by weight of the total composition with about 0.1% to about 0.8% being preferred and about 0.1% to about 0.5% being most preferred.
Perfumes (fragrance components) and colorants (coloring agents) well known to those skilled in the art may be used in effective amounts to impart tne desired fragrance and color to the compositions of this invention.
Other ingredients which may by added or used in amounts effective for their intended use include: biological additives to enhance performance or consumer appeal such as amino acids, proteins, vanilla, aloe extract, bioflavinoids, and the like; buffering agents; chelating agents such as EDTA;
emulsion stabilizers; pH adjusters; opacifying agents; and propellants such as butane carbon dioxide, ethane, hydrochlorofluorocarbons 22 and 1 42b, hydrofluorocarbon 1 52a, isobutane, isopentane, nitrogen, nitrous oxide, pentane, propane, and the li)<e.
The ingredients --sunscreening agents, emollients, emulsifiers, surfactants, solvents fo, sunscreening agents, waxes, thickeners, film formers, humectants, preservatives, wo9l/n7l6x l~crt-~sn/0632~

2068~7 -42 -surfactants, perfumes, coloring agents, biological additives, buffering agents, chelating agents, emulsion stabilizers, opacifying as~nts, pH adjusters, and propellants-- are all ~vell known to those skilled in the art, and the determination of which ingredients to use to obtain the intended formulations ~lotions, creams, gels, sticks, and aerosols), and determination of the variations in the amounts which may be used ~o achieve the intended functions and effects of these ingredients are well ~ ithin the c^~a~iliti~s of thcse skilled in the ar~ h~u~ .~,e t Q need for unc'ue sxperimQntation. Further information may be cbtainec` on ;"ese ingredien.s by ,e,erence .o:

( 1 ) Cosmetics & Toiletries, Vol. 102~ No. 3~ March 1 987;
(2) Balsam, M.S., et al~, editors, Cosmetics Science and Technology, 2nd edition, Vol~ 1, pp 27-104 and 179-222 Wiley-lnterscience, New York, 1 972;
(3) Cosmetics & Toiletries, Vol. 104, pp 67-1 11, February 1989;

(4) Cosmetics & Toiletries, Vol. 103, No. 12, pp 100-129, ~)ecember 1988; and (5) Nikitakis, J.M~, editor, CTFA Cosmetic Ingredient Handbrook, First Edition, published by The Cosmetic, Toiletry and Fragrance Association, Inc., Washington, D.C., 1988.

the disclosures of each being incorporated herein by reference thereto.
By using effective amounts of the exemplified 35 components various types of creams, lotions, gels, solid sticks, ~ (> 91/()71~Y ~ C r/~i9n/n632~;
` 2068427 and aerosol formulations can be blended in accordance with known compositions anà procedures. In making the formulations it is prelerred ;~ât .he ribo~lavin~ riboflavin phosphate or mixtures therQof not be sub~iected to heating or to high alkaline conùi~iolls. h rr~-~, Aotivators are used they should not be heated nior s ib,eo~ed 'o hi~h al!~aline conditions~
~o~ m :.le~ ~ ,ypical lo;ion formu'ation is listed in abie i W(.)91/(1/lfiX PC~ 9~ )32~i' 2~q27 - 44 -T~blel TYPICAL LQTION FORMUlATlC~
InQrp"~i~nt~ ~^ ~v Wt.
~Ll ~
Lanolin 0~2~o 1 io Cocoa autter 2.0o - 5%
Emcol RHT ~;lvceryl Steatate)l 2~0/o - 4O~o Hys;ren~ 5016 ~S~e~ric Acid~2 2.0o- 4%
Vitamin E ~csta;~ 0.1C^0~
Aloe ~era ~ uin~ne ~xlrac; 0.1o 1.0~o l^la'~ .! 0.1 - 1.0 Mineral Cil 1.0~c7O~o Prop~ipc,,a~,:,, 0.1c1~c ,~ledi~,ai ,-iuid ~,o~. iDim~thicone)3 3~1`,o ~

Water , 4 0 O - 60SO
Carbopol 941 (1%) ~Polyacrylic Acid 1 0O ~5,O
Polymer)4 Prop~!lene Glycol 2.0% - 7%
Triethanolamine 99% 0.1% - ~%
Lanogel 41 (PEG-75 Lanoiin)5 0.25% - 1%
Methylparaben 0.1% - 0.5%
Sequestrene Na2 0.01% - 0.08%
~L~
Perfume 0.01% - 0.5%
-Witco Corp., Organics Division, NY, NY (also Wi~conol RHT) 2 Humko Chemcal, Memphis, Tenn~
1 Q 3 Dow Corning Corp~, Midland, Michigan 4 B.F. Goodrich Specialty Polymers and Chemical Division, Cleveland, Ohio 5 Amerchol Corp~, Edison, NJ

To make the formulation listed in Table 1 parts 1 and 2 are heated separately to 180F. Part 1 is then added to Part 2 The resultant blend is cooled to 120F and Part 3 is then added.
A formulation containing riboflavin was prepared by combining the ingredients listed in Table 2.

W091/1)716X PC'r/~9n/n632%
2Q6~`27 Table 2 . _ . . .. ...

I ng re~il~ % Bv Vyt~
Part ,~
Alee ~vt~c~ 0~25 C~tYi ~lc~oi 4~00 ris~i ; h~ t~t~ 1 50 'rop~' P~,aben 0.1 0 `~Q~ lc~ oi 1 00 ~r B
)imethicor;e, 350 cst~ 0 60 Part ~
Glycerin, 99% 5.00 Me~thyl Paraben 0.20 dl-Panthenol 0.50 Sodium Lauryl Sulfate 0~40 Water, purified, USP 75~425 Part Q
I~nidazolidinyl Urea 0.30 RiboflaYin 0.20 Water 1 0.00 Part E
Benzyl Alcohol 0.50 Feltor~ Fra~tance #832 0 025 cst = centistokes (also abbreviated as ~cs") .....
The ingredients in Part A and Part C (Table 2) were heated to about 77-82C. Then Part A was stirred into Part C Part B was ~ ~o ~)l/n7l6x rc r/~9n/nfi32~
206~`27 added to the mixture formed from Parts A and C The resulting mixture of aarts A, C and B was force cooled to 65C~ The ingrec.ic~ alt 3 ~vere di~solved together and then added at about ~5 50C to the mixture of Parts A, C, and B To this 5 resu!tin~ ~i.Yt!!.a therQ was added the ingredients of Part E at about 42-~5~C~ and tne final mixture was mixed until the temp~r~ r? ~ ~he mi~re reached room temperature (about ~ 5 r~ ~
- ;al,n?ies Q, ,ormuiations which may prove useful 10 whlch ~.I'Q vil-ln~ aler crealns, oil-in-water ~otions, water-in-oii lotlon~ oii-ln wa~er resistant creams anb lolions, StiCKS~
gels~ oiis ana mousses may be tound in, for example, Cosmetics & Toiletries~ Voi 102, pp 1 17-130, March 1987, the ~isclosure of which is incorporated herein by reference thereto. Examples 1~ of formulations which may prove useful which are hand and body lotions, oil-in-water emollient creams, moisturizing lotions, after sun emollient stick, facial spray mist, skin mousse and moisturizing gel may be found, for example, in Cosmetics &
Toiletries, Vol. 102, pp 147-160, April 1987, the disclosure of 20 which is incorporated herein by reference thereto~ Those skilled in the art wiii appreciate that the formulations described in the above cited Cosmetics & Toiletries references (March and April 1987) represent types of formulations which may be suitably modified to allow for the addition of riboflavin, riboflavin phosphate or mix~ures thereof, and that such modifications may be accomplished without the need for undue experimentation.
The ~o!lowing examples are iilustrative only and should not be construed as limiting tne invention in any way.
Those skilled in the art will appreciate that variations are 3C possib!e which are within the spirit and scope of the appended claims .

~ !0 91/()716X~ r/~ ~9n/~632~i 20~8427 .EXA~ L~ l ir, ;nia e~:a",~ie .i,e a~ ;y of rlvOilaVin (O er,har,ce melanogenesis (tanning) was studied Compositions containing 5 ribofla~in in amounts af ? r,~^~ and 0.~o~ by we~3ht of the total composition (vehicle and riboflavin! were stl~ied The vehicle was Coppertone .~fte Tnn 1 a;ion~ cor~me~ l v av.ailable from P I ou 5 h I ~ ,A e ~ s, T `, . ~ ~? ~L' I~:i b similar ;,) ~ , c.~
Tinree gro~o~ of eme~ h-~ pl l .n,enieà hairiess mice, five mice per ar~ were s,~ie" Grouo 1 was tne con~ro and was treated with ~ne vehicle oniy Grour~ 2 was treated with the 0.02% riboflavin c mposition, and Group 3 was treated with 0.2% riboflavin compo:.ition Each group received topical 15 treatment daily (Mon~ay to Friday) to their dorsal surface (12 cm2) of 2 ~11/cm2 of the appropriate vehicle or composition for four weeks. Irratiiations were performed three times weekly (Monday, Wednesday and Friday) over the four week time period.
The irradiations were performed usir~g a 20 minute exposure 20 each time from a bank of Kodacel 401-filtered FS-20 lamps. The mice were housed in a room lighted by F40GO gold fluorescent lamps. The test solutions were stored refrigerated in the dark when not in use.
After four ~ eks analys`.s was performed by taking 25 histological sections from the midback of each mouse. DOPA
stains were done on epidermal sheets and Warthin-Starry melanin stains were done on thin sections in accordance with procedures well known to those skilled in the art (see, for example, Luna, L., Manual of Histologic Stainin~ Methods of the 30 Arrned ~orces Institute of Patholo~.. McGraw-Hill Book Co., New York, 1968. Ten random fields on DOPA stained sections were counted at 1 00x magnification and a group mean calculated.
Tests of melanocytes seen on Wa thin-Starry sections were scored from ~1 (a few melanocytes) to +4 (extensive U'O 91/(1716X 1~ 91)/llfi32t;

2~8~27 -48 -melani-a.io,) aî~d a me^-n score per slide for each group calcuated. The results are given in Table 3.
T~ble ~
... ..

Warthin-S.arrv OP~ '.rQ,.~le~ e~.nlS!lde) Control \vei-~ioi~ o~iy~ ~6 34 0 . 0 2, ~ , 3 ~

0.2% riboflavin 183 86 E~MPLE 2 The procedures of Example 1 were followed except that each group had 6 mice and the irradiations were conducted for three weeks. The results are given in Table 4.

Table 4 _ War~bin-St~rry Grg~ DQ~an) (Mean/~ide) Controi 54.8 28.2 0.02J~o riboflavin 47.0 29.8 0.2% riboflavin 98.0 70.6 .

WO 91/n716X r~r/~ ~)n/~)632x 49 2068~27 E~A~lP~
In this Example a study was conbucted to determine the tanning enhancement efficacv ~,~ o ~o~ !~o ~ n ~,~
Coppertone After Sun Lotion, (available from Pi^ugh Inc., 5 Memphis, TN, the composition of t"e ' 3.icn wvu!d be sin~,iia, t^
that given in Table 1 above) on human subje~ts The control was the Coppertone After Sun Lotion \NI'~I''OU~ vi!a~ Tl l_ C~2o riboflavin lotion was store^ in a da, ~ e~ n a!ne- ~e ers~,-e photostability Six voiunteers were selecle~ ~vit~ S~ yne~
Irradiation templates were devisQ~ with ~o ol^u!a! ~o!e~, one inch apar~, o, 2 cm diame~el __e , p, ov .In `r'~'O ~ e~ V n sites of 12.57 cm2 Each subject~s arm ~ ~s exa,~inei anà
templates were placed to expose sites ~ n the lightly pigmented, hairless, inside forearm Reference poi~ts outside the treatment area were marked with Castaderm for te,nplate alignment. The upper site, designated site 1, was s~aced approximately two inches from the inside bend of the elbow. The irradiation source was a bank of 4 Kodacel 401-filtered FS20 bulbs in a shuttered housing. The subject's skin was approximately 3 inches from the Kodacel filtered shutter. Both sites were irradiated simultaneously .
During week 1 of the study, the lotions were applied daily at 25 Ill/site (2~11/cm2) and air dried During weeks 2 and 3, the applications were followed after a mlnimum of 2 hours by irradiations which increased daily in time until an MED (minimal erythermal dose) was achieved. After each subject`s MED was reached,-that exposure was continued to the end of the study.
Erythema/tanning were scored visually during weeks 2 and 3 according to the following scale 0 = no difference from surrQunding skin 1 = slight erythema (pink) 2 = erythema (red) 3 = very slight tan wo 91/n716~; PC~ i9n/~)632x 2~'12 ~

4 = tar.
5 = medium brown tan ~ = C^~ hr~ n t~n 5 A "+" or ~ c,s ~,s~ c i"~Jic~i~ d,',~rein.,~s no~ one full grade apart.
Resui;s ajr ~e~ .oi~h in ~,sis 5 and 6. In Tables 5 and ~, I i.ndi~a~es ~ .,hio'~ as ~.ea~ wi~h the lotion containir.g ~.~0 ri~ofl^~;irn~ ~ in~,ca~es Site Il ~.vhich was the lQ controi~ ~nd coiumn ~ gi\~es Ine resuits o, the comparison o Sites I anr~ 71 in(:!iC~tin~ hich C`jtQ iS dar~er as scored by the inves~ig_~ r ~

wo sl/~7l6x ~ 9~ )63~X

T~
V~co[~ Qf Tar~ninQ~E~h~m .
lrrad.Subject 1 Subject 2 Sub!ec~ 3 D~ n ~ n Memorial Day 2 0 0 0 o 0 ~ 0 C C
3 0 0 0 o O O (~ C
4 0 0 C 0 C ~ C

.
.
8 0 0 0 o 0 0 0 J 0 9 3 3 1 o 0 0 0 ~ 0 3 3 I 0 0 0 0 ~ 0 12 3 3 I 0 0 0 ' 3 -- ---- ---- ~~ ~~ ~~ ~~ ~~ ~~
4 3 I 3 3 o 3 3 - 16 4 3 I dropped out 3 3 Il , :

Darkest Site: I Equal .
' Freckles Appeared wo 9l/n7l6~ T'~/~9n/~)632~

2 0 ~ 8 4 2 ~' - 52 -T,~ R ! ~
Visu21 Scorin~ oi T~nninoL,'. tv-~n~m~- (cor,t.) Irrad. Subject 4 S~b,e^~ 5 S~bject 6 DaY I n ~ , ' ^ 1 ~, c 2 0 0 3 v` ' ~, O O O
3 0 0 ~ `v ` v 3 0 Q
l 0 4 0 C C A ~ C V C
0 0 0 `i ~ O O
~ ~ ~ . . .

8 0 0 0 0 0 ~ 0 0 0 t5 9 0 Q 0 0 C 0 0 0 0 11 0 0~ 0 0 0 0 1 1-12 0' 0' 0 3 0 1 1- 0 . .

dropped out 4 3 1 4/1 3 ]
16 4- 3 ' 4/1 3 17 311 3- 1 411+ 3 4 3- 1 3+11- 3 Darkest ~e: I .
. .
Freckies Appeared WO 91/n~16X ~'C'l`/~i()n/()(32X
20~27 EXAMPL~4 Using the same experimental procedure set forth i~
Example 2, the effects of 0.01% (by weight) DOPA phO'`l.JllCI'`3 (mixture of Isomers Il and III, see U.S 4,508,706) were co"mpar~d 5 to a combination of 0.01% (by weight) DOPA ohosphate (mixtur~
of Isomers 11 and III) and 0.02% (by weight) riboflavin, and to a combination of 0 01% (by weight) DOPA phosphatQ (mixtu!e o Isomers II and III) and 0.2% by weight riboflavim All lo,ions we~.
stored refrigerated in the dark The resultc a!Q t~ en i~l ~'?~
Table ,9 Warthin-Starry ~QIIQ (Grol~e Mean) (Mean/Slide) Control- 54.8 28.2 0.01% DOPA phosphate 86~4 58.2 0.02% Riboflavin- 47.0 29.8 0.20% Ri~oflavin' 98.0 70.6 0.01% DOPA phosphate and 92 .4 56 . 8 0.02% Riboflavin 0.01% DOPAphosphate and 177.6 89.2 0.20% Riboflavin .
1~ Same as in Example 2 In an earlier experiment of Example 4 the group responding with the greatest pigmentation increase (melanocyte count) over the control group was tile group treated with 0.01 ~o 20 DOPA phosphate (mixture of Isomers Il and III) plus 0.2%

WO 91/1)716~ ~'C~r/~ X9~)/n632X
20~8~2 1 riboflavin. However, the response in tne ea uiQr ~xperimem could not be shown to be statis~ic^-!ly ditfer2r,t " ~m the response due to 0.2% ribo,.a~/in non~ e ~-?n -ue :r~
the degradation of DOPA phospna~e isomer ii sinc~ the lotion was 6 not stored refrigerated in the ea, iie, e`~O?, ime!1t~ e di"ere"ce in the results set forth in I ab~e , are slai~ist,caiiy significan~
Those skilled in ~e s~r~ ''!j'j "``~-~''`I'~`~`'a~e '~ h~ o~
amount of all ingredients (coi~ o!`~ s~ u~eà in `ne eO'n`OOà'.rion`
of this invention equals 1~ ~ ~y ~ ig~+ ~
10 composition. Also~ uniess s~at~e otn ~ e - ' , ~, s~ d amounts are perc~nt b~ ai~h~ ~hi ~e~
The invenlion veing ;nilà ~àori~o, i, ~,viii o~ OVViOUâ
that the same may be varied in many ways~ ~uch variations are not to be regarded as a departure from the spirit and scope o 15 the invention and al! such modifications are intended to be included within the scope of the claims~

Claims (15)

WHAT IS CLAIMED IS:

1. A composition comprising riboflavin, riboflavin phosphate or mixtures thereof in an amount effective to enhance melanin production when said composition is applied topically to the skin.

2. The composition of Claim 1 wherein said composition comprises about 0.1% to about 2% by weight of the total composition of riboflavin, riboflavin phosphate or mixtures thereof.

3. The composition of Claim 2 wherein said riboflavin, riboflavin phosphate or mixtures thereof are encapsulated in liposomes.

4. The composition of Claim 2 wherein said composition comprises an effective amount of water and an effective amount of a humectant.

5. The composition of Claim 1 wherein there is added to said composition an effective amount of at least one other ingredient selected from the group consisting of: Protein Kinase C Activators, DOPA phosphates, sunscreening agents, emollients, emulsifiers, solvents for sunscreening agents, waxes, thickeners, film formers, humectants, antioxidants, preservatives, surfactants, skin penetration enhancers, perfumes, biological additives, buffering agents, chelating agents, emulsion stabilizers, opacifying agents, pH adjusters, propellants and coloring agents.

6. The composition of Claim 2 wherein there is added to said composition an effective amount of at least one other ingredient selected from the group consisting of Protein Kinase C Activators, DOPA phosphates, and sunscreening agents .

7. The composition of Claim 8 wherein the Activator is selected from the group consisting of diacylglycerols, triacylglycerols, lipopolysaccharides, unsaturated free fatty acids, saturated short chain free fatty acids, glycerolphospholipids, enzymes which hydrolyze glycophospholipids to diacylglycerols, and bry????????.

8. The composition of Claim ? wherein diacylglycerol is added to said composition.

9. The composition of Claim 8 wherein said diacylglycerol is selected from the group consisting of:

(a) 1,2-dioctanoyl glycerol;
(b) 1,2-didecanoyl glycerol;
(c) 1-oleoyl-2-acetyl glycerol;
(d) 1-acetyl-2-oleoyl glycerol;
(e) 1,2-dihexanoyl glycerol;
(f) 1-stearyl-2-arachidonyl glycerol;
(g) 1-stearyl-2-oleoyl glycerol;
(h) 1,2-dipalmitoyl glycerol;
(i) 1,2-distearyl glycerol;
(j) 1,2-dioleoyl glycerol;
(k) diarachidonin;
(l) diolein;
(m) dipalmitin; and (n) distearin.

10. The composition of Claim 8 wherein said diacylglycerol is a diacyl-sn-glycerol.

11. The composition of Claim 10 wherein said diacylglycerol is 1,2-dioctanoyl-sn-glycerol.

12. A method of enhancing melanin production comprising applying topically to the skin a composition of any of Claims 1-11.

13. The use of a composition of any of Claims 1-11 to manufacture a composition for enhancing melanin production when applied topically to the skin.

14. The use of a composition of any of Claims 1-11 to enhance the production of melanin when said composition is applied topically to the skin.

15. A process for producing a composition for enhancing melanin production when said composition is applied topically to the skin comprising combining riboflavin, riboflavin phosphate or mixtures thereof with suitable solvents.