The Articles of Confederation and Constitution did not attempt to provide voting or other rights to women, the poor, or slaves. The Constitution, for example, counts slaves as three-fifths of a person for the purposes of levying taxes and proportioning representation in the House of Representatives, but slaves could not vote. Slavery was not abolished until after the Civil War, and consideration of the slave trade was put off until 1808 (the Constitution was ratified in 1788). In addition, women were not allowed to vote, and voting rights were extended to white men with property.
The failure of the Constitution and Articles of Confederation to address inequality affected the structure of our government. For example, as stated above, slaves only counted for three-fifths of a person in figuring out how many representatives were elected from each state. In addition, in the original Constitution, senators were chosen by state legislatures (composed generally of wealthier white men in those days) rather than directly by the people. People only began to directly elect senators with the passage of the 17th Amendment in 1913.
It would take a long time for disenfranchised groups to be represented in the national government. The Constitution allowed slavery to continue, and it did continue until the end of the Civil War and the ratification of the 13th Amendment in 1865. African-American men gained the right to vote in 1870 with the 15th Amendment, but in many places in the South, most African-Americans were denied the right to vote until the 1960s. In addition, women did not gain the right to vote in national elections until the 19th Amendment was ratified in 1920.