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I have two questions regarding L-Tryptophan.

Question 1

I need to draw an alternative resonance structure which begins with "the ring nitrogen". 

I have attached my idea for the first one. 
I drew a picture that shows electron movement.  In the left picture, a lone pair on nitrogen begins to shift to the left and pushes the pai bond to the adjacent carbon (which will give a negative charge).   This will continue to shift around the cyclohexene and further to the adjacent ring.  This nitrogen heterocycle is attached to the amine and carboxylic group, but since the closest carbon is sp3, the electrons will not be transferred other than the rings.  So, the electron shift will come back to the nitrogen.  And I drew the alternative structure.  Overall, the pai bonds are moved to the next bonds.  What do you think?

Question 2, I need to assign each pKa value to the correct hydrogen.

I see in my textbook about pKa values assigned to COOH and +NH3 as 2.38 and 9.39 respectively.  But I also see the secondary nitrogen in the nitrogen heterocycle.  Do I need to consider the nitrogen also?  I see the pKa value for the secondary nitrogen in the ring as -2.4 in my textbook...

I really appreciate all of your *delete me*  Happy Thanksgiving!

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I haven't heard anything yet...but if anyone has any comments..I would love to hear them.

Please let me know if I didn't put enough information for you to reply...and I will add it!

Thanks in advance.