(S)-3′-methyl-abscisic acid and esters thereof

1. A compound of Formula I:

wherein R is hydrogen, substituted or unsubstituted alkyl, cycloalkyl, heterocycloalkyl, alkenylalkyl, alkynylalkyl, alkenyl, cycloalkenyl, heterocycloalkenyl, alkynyl, aryl, heteroaryl, arylalkyl, or heteroarylalkyl;

and salts thereof.

2. The compound of claim 1 wherein R is hydrogen.

3. The compound of claim 1 wherein R is alkyl.

4. The compound of claim 3 wherein R is lower alkyl.

5. The compound of claim 3 wherein R is substituted with at least one of —OH, —NH 2 , —SH, halogen, —CN, —NR 1 R 2 , —OR 1 , —SR 1 , —S(O)R 1 , —SO 2 R 1 , —C(O)R 1 , —C(O)NR 1 R 2 , —NHC(O)R 1 , —NHSO 2 R 1 , —NHC(O)OR 3 , —SO 2 NR 1 R 2 , or —NHC(O)NR 1 R 2 wherein R 1 and R 2 are each independently hydrogen or lower alkyl and R 3 is lower alkyl.

6. The compound of claim 1 wherein the salt comprises an alkali or alkaline earth metal cation, protonated amine ( + NHR 4 R 5 R 6 ) wherein R 4 , R 5 , and R 6 are each independently hydrogen, lower alkyl, aralkyl or a quaternary ammonium ion ( + NR 7 R 8 R 9 R 10 ) wherein R 7 , R 8 , R 9 , and R 10 are each independently lower alkyl or lower aralkyl.

7. The compound of claim 1 wherein the salt comprises an inorganic anion selected from the group consisting of chloride (Cl − ), bromide (Br − ), iodide (I − ), sulfate (SO 4 2− ), and bisulfate (HSO 4 −), or an organic anion selected from the group consisting of formate (HCO 2 − ), acetate (CH 3 CO 2 − ), tartrate ( − CO 2 CH(OH)CH(OH)CO 2 − ), methanesulfonate (CH 3 SO 3 − ) and tolylsulfonate (CH 3 C 6 H 4 SO 3 − ), and wherein R contains a basic nitrogen atom.

8. A method of regulating plant growth in Arabidopsis comprising applying an effective amount of the compound of claim 1 to an Arabidopsis plant in need of growth regulation.

9. A process of making the compound of claim 1 comprising:

a. reacting (S)-abscisic acid with an alkylating agent to form an ester;

b. treating the compound resulting from Step a with a base and methylating agent in a solvent;

c. and optionally hydrolyzing the compounds resulting from Step b.