Dispute over distribution of ancestral agricultural land.

We are six brothers in all and I am the eldest . I am a retired person of 75 years of age and also a heart patient. Both of our parents have died , We own joint ancestral agricultural land situated and registered in the revenue records of village Khandeha, Tehsil Khair, Distt. Aligarh, U.P. Initially one of our brothers sold a portion of the land before final distribution and legal mutation among all the six brothers, to the wives of two other brothers secretly without the knowledge and consent of remaining three other brothers including me . The portion so sold by one brother is meant to threaten the irrigation facilities of the remaining portion pertaning to other brothers Now all my five brothers have jointly made a compact to harm me. They have jointly and unjustifiably allocated/ allotted to me the worst position of the said land which is less in proportionate area and of low sale value because of the fact that convenient and effective irrigation drainage system does not have access to this area for irrigation purpose. You are requested to advise me as to what I should do to get justice i.e. how to get a portion of equal proportionate area and sale value and also with suitable and effective irrigation drainage system approaching the same.