अन्वयः

दुरात्मना by the wicked self, रावणेन by Ravana, तस्य his, वधे killing, समाज्ञप्ते when ordered, विभीषणः Vibhishana, दौत्यम् message, निवेदितवतः who had declared (the purpose of his visit), नानुमेने did not approve.

M N Dutt

On the death of that one who had proclaimed his own position of being an envoy, having been ordered by the wicked-minded Ravana, Vibhisana did not agree (with the decision).

Summary

Vibhishana did not approve of the killing of Hanuman, who had declared that he was an envoy (of Sri Rama) when the wicked Ravana ordered his murder.

पदच्छेदः

वधे	वध (७.१)
तस्य	तद् (६.१)
समाज्ञप्ते	समाज्ञप्त (√समा-ज्ञपय् + क्त, ७.१)
रावणेन	रावण (३.१)
दुरात्मना	दुरात्मन् (३.१)
निवेदितवतो	निवेदितवत् (√नि-वेदय् + क्तवतु, ६.१)
दौत्यं	दौत्य (२.१)
नानुमेने	न (अव्ययः)–अनुमेने (√अनु-मन् लिट् प्र.पु. एक.)
विभीषणः	विभीषण (१.१)

छन्दः

अनुष्टुप् [८]

छन्दोविश्लेषणम्

१	२	३	४	५	६	७	८
व	धे	त	स्य	स	मा	ज्ञ	प्ते
रा	व	णे	न	दु	रा	त्म	ना
नि	वे	दि	त	व	तो	दौ	त्यं
ना	नु	मे	ने	वि	भी	ष	णः