として〜ない details
Examples
not a single — formal, written-register negation that exhausts every member of a counted set, most often a counted person or instance
その提案に対して、委員はだれ一人として異論を唱えなかった。
sono teian ni taishite, iin wa dare hitori to shite iron o tonaenakatta.
Not a single committee member raised an objection to the proposal. formal
展示された作品の中で、二つとして同じものはなかった。
tenji sareta sakuhin no naka de, futatsu to shite onaji mono wa nakatta.
Among the exhibited works, no two were alike. neutral
Formation
数量詞＋として…ない（一人として・一つとして）attaches to noun phrase (schematic)
Notes
"no two alike" reading takes 二つとして instead. The clause it reaches
must stay negative throughout, or a bare, ungrammatical role-marker として is all that is left.
Related patterns
Similar
Both push toward an extreme "not even" reading, but さえ〜ない singles out one minimal, least-likely case and denies just that (一円さえない, doesn't even have one yen), while 一人として〜ない sweeps across every member of a counted GROUP and denies each in turn (だれ一人として賛成しなかった) — さえ picks the extreme instance, として exhausts the whole set.
Lookalikes
Bare として ordinarily marks a ROLE or capacity (大人として "as an adult") and carries no negation of its own; fused onto a counter it instead reaches for a distant ない, so 一人としてXない is not "as one person, not X" but "not a single person Xed" — misreading として as the role-marker loses the totalizing negation entirely.