Compounds and methods relating to lysosomal storage disorders

1. A molecule comprising the formula:

where B1 is selected from the group consisting of: a methylene or an unsubstituted C 6 aryl;

B2 is a C 2 -C 7 chain comprising an amido, a urethane, an ester, a uriedo, a carbmamato, or a carbonyl bond to said molecule, wherein said C 2 -C 7 is unsubstituted, or wherein when said C 2 -C 7 comprises an alkyl or alkenyl chain, said B2 is unsubstituted or comprises a heteroatom or a substituent of N, O, or S, and wherein when said B2 is bonded by an amido, that said B2 is a C 3 , C 5 , or C 7 amido; and

B3 is selected from the group consisting of: an unsubstituted C 1 -C 20 alkyl, a heteroatom containing C 1 -C 20 alkyl; a C 1 -C 20 alkyl substituted with N, O, or S; an C 2 -C 20 alkenyl; a heteroatom containing C 2 -C 20 alkenyl; an C 2 -C 20 alkenyl substituted N, O, or S; an unsubstituted C 2 -C 20 alkynyl; a heteroatom containing C 2 -C 20 alkynyl; a C 2 -C 20 alkynyl having substitution of N, O, or S; an C 6 -C 20 aryl; and an C 6 -C 20 heterocyclic containing a heteroatom of N, O or S;

the molecule comprising a label, the label comprising a stable isotope of an element on said B2 or B3.

2. The molecule of claim 1 , wherein said stable isotope is selected from the group consisting of 2 H, 13 C, 15 N, 17 O, 18 O, 31 P and 34 S.

3. The molecule of claim 1 , wherein B1 is a methylene.

4. The molecule of claim 1 , where B2 is a C 3 amido, a C 5 amido, or a C 7 amido.

5. The molecule of claim 1 , wherein B3 is a C 2 -C 20 alkenyl having a substituent of N, O, or S.

6. The molecule of claim 1 , wherein: B1 is a methylene; B2 is a C 3 amido, a C 5 amido, or a C 7 amido; and B3 is a C 2 -C 20 alkenyl having a substituent of N, O, or S.

7. The molecule of claim 1 comprising:

8. The molecule of claim 1 , wherein said stable isotope is present on said B2.

9. The molecule of claim 8 , wherein said stable isotope is present on a terminal carbon, α-carbon, or a combination thereof.