( ( ( ( ( ( The ( two trans ) ) ( alkenes ( react head-to-tail ) ) ) , ) and ) ( ( the ( isolated isomers ) ) ( are ( called ( truxillic acids ) ) ) ) ) . )
(ROOT (S (S (NP (DT The) (CD two) (NNS trans)) (VP (VBZ alkenes) (VP (VB react) (NP (NN head-to-tail))))) (, ,) (CC and) (S (NP (DT the) (VBN isolated) (NNS isomers)) (VP (VBP are) (VP (VBN called) (NP (JJ truxillic) (NNS acids))))) (. .)))
The two trans alkenes react head-to-tail, and the isolated isomers are called truxillic acids.
(ROOT (S (NP (NP (NNS Alkenes)) (PP (IN with) (NP (NP (DT the) (JJ same) (NNS atoms)) (PP (CC but) (NP (JJ different) (NNS shapes)))))) (VP (VBP are) (VP (VBN called) (NP (NNS isomers)))) (. .)))