Joining tables

[#1]

I have to join two tables  using jsl. The first table looks like this:

 

However, the second table can either be like this:

 

In this table, Pred Form Molecule 1 (%)(2) is the same as Molecule 1(%) and the numbers in the value column are repeated. How can I specify the join to only consider one of those values?

The second table to join can look like this:

In this case, how can I specify in the join that Molecule 1 (%) in the first table is the same as Pred Form Molecule1 (%)(2) in the table that needs to be joined. 

The final table that I need should be something like this:

 

Thank you for any help.

[#2]

You can use the Search(Find) dialog to change column names, or parts of column names

[#3]

@txnelson & @pmroz, 
     If I may, I would like to ask one question, why would you recommend column names be recoded / renamed given the table structure?  The current structure of the table shared shows that the data is in the rows. While I understand, that one can always transpose the data and rename columns, wondering if that is the approach you are recommending ? Please advice 

[#4]

I was suggesting recode to change values in a column, not change the name of the column.  To use the recode option, highlight the column you wish to recode, and click on Cols > Utilities > Recode (v12) or Cols > Recode (v13).

[#5]

@pmroz, 
    Thank you for clarifying. My bad, was wondering if there was a better way to approach this that I was missing. 

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@pmrozwrote:

I was suggesting recode to change values in a column, not change the name of the column.  To use the recode option, highlight the column you wish to recode, and click on Cols > Utilities > Recode (v12) or Cols > Recode (v13).

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