Is there any syntactic analyzer for English?
Perhaps not exactly what you’re after, but interesting none the less, check out SYCORAX: An Automated Analyzer of the Syntactic Complexity of English Text (2011) by William Cody Boisclair:
SYCORAX, like several prior applications for automated analysis of syntactic complexity (e.g., Long et al., 2006; Channell, 2007; MacWhinney, 2011), is based on the Developmental Sentence Scoring (DSS) scale developed by Lee (1974). These existing applications, however, all have one significant limitation in common: they are all strictly based on immediate linear context within a sentence. It is evident from prior work (Channell, 2003; Judson, 2006) that certain syntactic structures involved in DSS are simply not apparent from linear context alone; indeed, many structures incorrectly analyzed by human raters are due to incorrect interpretation of local context (Lively, 1984).