Italian chemist and American doctor in turn avoid putting out papers at the beginning (8)
I believe the answer is:
avogadro
'italian chemist' is the definition.
The definition suggests a singular noun which matches the answer.
'american doctor in turn avoid putting out papers at the beginning' is the wordplay.
I cannot really see how this works, but
'american' could be 'a' (common abbreviation - e.g. in organisation names) and 'a' is located in the answer.
'doctor' could be 'dr' (abbreviation) and 'dr' is found in the answer.
This may be the basis of the clue (or it may be nonsense).
'and' acts as a link.
Can you help me to learn more?
(Other definitions for avogadro that I've seen before include "scientist" , "Italian physicist giving name to a constant" , "Italian gas physicist" .)