It has been studied and the recommended approach is 2g in the morning and 2g in the evening to get a full 24 hour effect. 

Refer to

Finding the best therapeutic approach for PCOS: the importance of inositol(s)bioavailability.

• B. Orrù, R. Circo, G. Carlomagno
• Published 1 June 2017
• European review for medical and pharmacological sciences.