Neither of them is exactly what you’re looking for, but you might be interested in lojban, which aims to be syntactically unambiguous, and Ithkuil, which aims to be extremely information-dense as well as to reduce ambiguity. With regards to logical languages (ones which, like lojban, aim for each statement to have a single possible interpretation), I also found Toaq and Eberban just now while looking up lojban, though these have fewer speakers.
Neither of them is exactly what you’re looking for, but you might be interested in lojban, which aims to be syntactically unambiguous, and Ithkuil, which aims to be extremely information-dense as well as to reduce ambiguity. With regards to logical languages (ones which, like lojban, aim for each statement to have a single possible interpretation), I also found Toaq and Eberban just now while looking up lojban, though these have fewer speakers.