Earlier quoted context omitted.
I don't quite understand your question. You are asking what Iran wanted from the EU and US and what they wanted from Iran? EU&US: Don't develop nuclear weapons. Iran: Stop the sanctions, let us sell our oil. Is that what you were asking for?
I don't understand why there were negociation at all. Usually, with such crucial matters, threatening the world peace, there is no discussion. The strongest simply impose its decision. Eu&us: stop or you'll get destroyed ( militarely or economically). Iran : ok. I don't see how it went any other way. The only reason i could imagine was if other big countries ( russia and china mainly) were saying " we disagree". But…
Presumably the alternative is to threaten to invade or impose economic sanctions, but that doesn't seem to me like the beginning of a productive conversation. If anything it might increase the urgency of getting weapons, of any type, to be taken seriously.