Here is a basic skin lightening formula for making a creme containing Undecylenoyl Phenylalanine also known by it's brand name Sepiwhite. Undecylenoyl Phenylalanine has been tested and has shown comparable results to be stronger than hydroquinone, Kojic Acid, and Alpha Arbutin.

Description: Unique skin lightening agent made of natural amino acids with a lipid-residue. White powder. Insoluble but miscible in water, soluble in alcohol. CAS# 175357-18-3.
INCI Name: Undecylenoyl phenylalanine.
Properties: Inhibits skin cells to produce melanin pigments by inhibiting melanin-stimulating MSH (melanotropin), effectively lightens age spots & dark skin areas. Requires application of 1 to 6 weeks until skin whitens dependent on skin pigmentation. Product has excellent stability in cosmetics not leading to change in colors.
Use: Recommended use level 1-2%, must be melted for use (best in oil phase of formula at 80oC/176oF). Optimal pH <5 or >6.2 for best incorporation into formulas.
Application: All kinds of skin-lightening products including lotions, creams, fluids, makeup products.

Phase A	Weight %	For 100 g /3.6 oz (by weight)
Distilled Water (diluent)	80.5%	80.5 g / 2.9 oz
Phase B
Emulsifying Wax (CreamMaker Wax, emulsifier) Meadowfoam Seed Oil (emollient) Vitamin E Acetate (antioxidant) SkinWhite MSH (skin- whitener) GelMaker EMU (thickener/emulsifier)	2 % 12 % 0.5 % 2 % 2 %	2 g / 0.1 oz/ 1 tsp 12 g / 0.4 oz 0.5 g / 12 drops 2 g / 0.1 oz / 1 tsp 2 g / 0.1 oz 3/4 tsp
Phase C
Paraben- DU (preservative)	1 %	1 g / 0.04 oz / 1/4 tsp or 22 drops

Method
Add phase B into a disinfected, heat- resistant glass beaker and heat to 80- 85C/180- 185F, stir, make sure the Skinwhite MSH is melted. Add phase A to another disinfected glass beaker and heat to the same temperature. Remove both beakers from the heat. Add phase A to phase B and stir well, to form the cream. Add phase C when the temperature has cooled to 100F/40C, then stir again well before filling into jars.

Properties
Novel unique skin lightening agent (undecylenoyl phenylalanine), made of natural amino acids with a lipid- residue. inhibits skin cells to produce melanin pigments by inhibiting melanin- stimulating MSH (melanotropin), effectively lightens age spots & dark skin areas. Requires application of 1 to 6 weeks until skin whitens dependent on skin pigmentation. Product has excellent stability in cosmetics not leading to change in colors.

This is a good compounding formula. Maybe add more sepiwhite to be more effective but still in the safe zone for the skin and AHAs to speed the lightening process.