

In English, it’s a matter of honor to mangle foreign loan words, unless you’re the kind of twit who pedantically pronounces foreign words as though you’re not speaking English, but the language of origin. That’s most common with French loanwords, since French was once considered higher-prestige than English. But I’ve even heard people attempting to pronounce Arabic words like that, despite having no idea of Arabic phonology or case inflection, with ridiculous results.
In ancient Greek, as best we can tell. The “i” is more like “ee” as well. In English, it’s “die-no-sore” unless you’re non-rhotic, and if you are, then piss off, you posh ponce.