https://www.synzeal.com/efavirenz-ethene-analog-3

Там вроде единственное отличие - вместо алкиновой связи - алкеновая.

Может быть, pentenein правильнее?

I think your translation is correct and professional (it’s a rarity here), but there are a few things here I’d like to mention:

(4S)-6-Хлор-4-(циклопропилэтинил)-1,4-дигидро-4-(трифторметил)-2H-3,1-бензоксазин-2-он
Эфавиренз – in Russian sources? Well, not precisely; it is actually efavirenz ethene analog!

So what is эфавиренз then? Here comes this guy:
Efavirenz Эфавиренз
(4S)-6-chloro-4-(2-cyclopropylethynyl)-4-(trifluoromethyl)-1H-3,1-benzoxazin-2-one
(4S)-6-хлор-4-(2-циклопропилэтинил)-4-(трифторметил)-1H-3,1-бензоксазин-2-он
Synonym: (s)-6-chloro-4-cyclopropylethynyl-4-trifluoromethyl-1,4-dihydro-2H-3,1-benzoxazin-2

Efavirenz ethene analog Эфавирензэтен аналог (=эфавирензэтилен аналог).
(S)-6-Хлор-4-(cyclopropylethynyl)-1,4-dihydro-4-(trifluoromethyl)-2H-3,1-benzoxazin-2-one
(S)-6-Chloro-4-(циклопропилэтинил)-1,4-дигидро-4-(трифторметил)-2H-3,1-бензоксазин-2-он
Synonym: (S,E)-6-Chloro-4-(2-cyclopropylvinyl)-4-(trifluoromethyl)-2H-3,1-benzoxazin-2-one
(S,E)-6-хлор-4-(2-циклопропилвинил)-4-(трифторметил)-2H-3,1-бензоксазин-2-он
Synonym: 1H-Benzo[d][1,3]oxazin-2(4H)-one, 6-chloro-4-cyclopropylethynyl-4-trifluoromethyl

Efavirenz penteneyne. Probable translation: Эфавирензпентенеин. Anyway, it’s impossible to find any info in Russian on this drug.
(S)-6-Chloro-4-(3-methylbut-3-en-1-ynyl)-4-(trifluoromethyl)-2H-3,1-benzoxazin-2-one
I’m leaving the full name without a translation because methylbut is tricky; probably should be translated метилбут. At least it keeps things chemically straight.

This one is easy to translate:
Efavirenz amino alcohol methyl carbamate Эфавирензаминоспиртметилкарбамат
(S)-Methyl 4-chloro-2-(4-cyclopropyl-1,1,1-trifluoro-2-hydroxybut-3-yn-2-yl)phenylcarbamate
But the full thing is tough again with 2-hydroxybut-3-yn-2-yl being a headache. My best guess is 2-гидроксибут-3-ин-2-ил.

My main piece of advice is to add or to leave the full names.
These two websites might be helpful:
http://charchem.org/ru
http://www.drugfuture.com/Pharmacopoeia/USP35/data/v35300/usp35nf30s0_m4628.html
Hope my input was of some help.

“Moderation in all things, especially moderation.”