What is the assembly of notables, 1787
The Assembly of Notables was not an American meeting. It was a French meeting.
The King, under the abolutist system that had run France for centuries, could call together prominent people to advise him. As the American Revolution began to inspire people throughout Europe to demand a role in government, Louis XVI realized that unless he did something to appease the masses, he might have a revolution in France as well. (Of course we know this only delayed the inevitable.) Louis felt that by gathering the "notables" which were among the elite of the country that they could work out a plan to maintain his rule. But he found that many of the notables demanded a role in government and the Assembly of Notables of 1787 marked the beginning of the end for Louis and Marie who had trouble hanging on to their rule...and eventually their heads.
One possible answer to your question would be that 1787 was the year in which the United States Constitution was written. The individuals who gathered in Philadelphia to undertake that process could certainly be described as including notables.
The Constitutional Convention ran May 25-September 17. During that hot, humid summer, delegates struggled to work out changes to the governmental system that had been created with the Articles of Confederation. After much debate and compromise, the eventual outcome was a completely new governmental structure, as established in the Constitution.
Delegates to the Convention included George Washington, James Madison, Benjamin Franklin, Robert Morris, Gouverneur Morris, William Livingston, Roger Sherman, and many other leaders of the Revolution and early years of the new country.