The present invention relates to a process for preparing the hexanoic acid, 6-(nitrooxy)-, (1S,2E)-3-[(1R,2R,3S,5R)-2-[(2Z)-7-(ethylamino)-7-oxo-2-hepten-1-yl]-3,5-dihydroxycyclopentyl]-1-(2-phenylethyl)-2-propen-1-yl ester of formula (I).

##STR00001##

In accordance with the present invention, the compound (I) can be efficiently prepared with high purity by coupling bimatoprost in a boronate protected form with 6-(nitrooxy)hexanoyl chloride and removing the boronate protecting group.

The 6-(nitrooxy)hexanoyl chloride intermediate is prepared by ring-opening reaction of 2-caprolactone and subsequent nitration of the 6-hydroxyhexanoic acid potassium salt with a mixture of HNO.sub.3 and H.sub.2SO.sub.4 in dichloromethane.

A method for producing an alkyl nitrite by bringing an aqueous solution containing nitric acid and an alkanol into contact with a gas including nitrogen monoxide and thereby producing an alkyl nitrite, in which the reaction temperature is 60 C. to 100 C., is provided.

A method for producing an alkyl nitrite by bringing an aqueous solution containing nitric acid and an alkanol into contact with a gas including nitrogen monoxide and thereby producing an alkyl nitrite, in which the reaction temperature is 60 C. to 100 C., is provided.

The present invention relates to a process for the preparation of -methyl-[4-(nitro)-2-(trifluoromethyl)]-benzyl nitrate and to the -methyl-[4-(nitro)-2-(trifluoromethyl)]-benzyl nitrate.

The present invention relates to a process for the preparation of -methyl-[4-(nitro)-2-(trifluoromethyl)]-benzyl nitrate and to the -methyl-[4-(nitro)-2-(trifluoromethyl)]-benzyl nitrate.

The invention relates to a safe and efficient process for the for the acylation of an ,-alkanediol, which can be used in the manufacture of -nitrooxy-C.sub.3-10alkane-1-ols. The process is safer to operators and allows to obtain advantageous yields on industrial scale.

The invention relates to a safe and efficient process for the for the acylation of an ,-alkanediol, which can be used in the manufacture of -nitrooxy-C.sub.3-10alkane-1-ols. The process is safer to operators and allows to obtain advantageous yields on industrial scale.

The invention relates to a safe and efficient process for the nitrate ester formation of an ,-C.sub.3-10alkanediol monoacylate. The process is safer to operators and allows to obtain advantageous yields on industrial scale.

The invention relates to a safe and efficient process for the nitrate ester formation of an ,-C.sub.3-10alkanediol monoacylate. The process is safer to operators and allows to obtain advantageous yields on industrial scale.