अन्वयः

शुना by a dog, शार्दूलयोरिव like two tigers, रामलक्ष्मणयोः of both Rama and Lakshmana, गन्धम् smell, उपाघ्राय smelling, त्वया by you, सन्दर्शने in their sight, स्थातुम् to stand there, न शक्यं हि it will not be possible.

M N Dutt

O Rākṣasa, those two lions among men going out to enquire about the illusive deer, I was ravished by you, entering the empty hermitage O vile wight. And like to a dog incapable of standing before a tiger, it would have been impossible for you, to wait there in the presence of Rāma and Laksmana.

Summary

"Had you smelt the presence of Rama and Lakshmna, it would not have been possible for you to stand there, like a dog under the gaze of a pair of tigers.

पदच्छेदः

न	न (अव्ययः)
हि	हि (अव्ययः)
गन्धम्	गन्ध (२.१)
उपाघ्राय	उपाघ्राय (√उपा-घ्रा + ल्यप्)
रामलक्ष्मणयोस्त्वया	राम–लक्ष्मण (६.२)–त्वद् (३.१)
शक्यं	शक्य (१.१)
संदर्शने	संदर्शन (७.१)
स्थातुं	स्थातुम् (√स्था + तुमुन्)
शुना	श्वन् (३.१)
शार्दूलयोर्	शार्दूल (६.२)
इव	इव (अव्ययः)

छन्दः

अनुष्टुप् [८]

छन्दोविश्लेषणम्

१	२	३	४	५	६	७	८
न	हि	ग	न्ध	मु	पा	घ्रा	य
रा	म	ल	क्ष्म	ण	यो	स्त्व	या
श	क्यं	सं	द	र्श	ने	स्था	तुं
शु	ना	शा	र्दू	ल	यो	रि	व