The invention provides compounds of formula (I): or a salt thereof as described herein. The invention also provides pharmaceutical compositions comprising a compound of formula (I), processes for preparing compounds of formula (I), intermediates useful for preparing compounds of formula I and therapeutic methods for treating a Retroviridae viral infection including an infection caused by the HIV virus.

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The invention provides compounds of formula (I): or a salt thereof as described herein. The invention also provides pharmaceutical compositions comprising a compound of formula (I), processes for preparing compounds of formula (I), intermediates useful for preparing compounds of formula I and therapeutic methods for treating a Retroviridae viral infection including an infection caused by the HIV virus.

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The present invention is related to a method for increasing the trans-specificity of a beta-carotene oxidase (BCO), particularly insect BCO, to be used in the production of vitamin A aldehyde (retinal) from conversion of beta-carotene, with at least about 75 to 100% of retinal in the trans-isoform.

The present invention relates to a new compound and the dehydrogenation of that compound to produce retinal.

The present invention relates to a new method to produce 7,8-dihydro-C.sub.15-aldehyde.

The present invention relates to a new method to produce 7,8-dihydro-C.sub.15-aldehyde.

The present invention relates to an improved method for producing specific α,β-unsaturated aldehydes.

The present invention relates to an improved method for producing specific α,β-unsaturated aldehydes.

The present invention relates to a new process for the production of retinal or hydrogenated form of retinal.

The present invention relates to a new process for the production of retinal or hydrogenated form of retinal.