The Dimethyl methyldopa, with the CAS registry number 115217-60-2, is also known as (2S)-2-amino-3-(3,4-dimethoxyphenyl)-2-methyl-propanoic acid trihydrate. This chemical's molecular formula is C₁₂H₁₇NO₄· 3/2 H₂O and molecular weight is 532.26. What's more, its systematic name is 3-Methoxy-O,α-dimethyl-L-tyrosine hydrate (2:3). 

Physical properties of Dimethyl methyldopa are: (1)ACD/LogP: 1.2; (2)# of Rule of 5 Violations: 0; (3)#H bond acceptors: 5; (4)#H bond donors: 3; (5)#Freely Rotating Bonds: 6; (6)Polar Surface Area: 48 Å²; (7)Flash Point: 183.4 °C; (8)Enthalpy of Vaporization: 66.21 kJ/mol; (9)Boiling Point: 379.6 °C at 760 mmHg; (10)Vapour Pressure: 1.93E-06 mmHg at 25°C.

You can still convert the following datas into molecular structure:
(1)SMILES: O=C(O)[C@](N)(C)Cc1cc(OC)c(OC)cc1.O=C(O)[C@](N)(C)Cc1cc(OC)c(OC)cc1.O.O.O
(2)Std. InChI: InChI=1S/2C12H17NO4.3H2O/c2*1-12(13,11(14)15)7-8-4-5-9(16-2)10(6-8)17-3;;;/h2*4-6H,7,13H2,1-3H3,(H,14,15);3*1H2/t2*12-;;;/m00.../s1
(3)Std. InChIKey: POPVPGCSVATVRH-MKYDYASUSA-N