The invention comprises ethers of formula: <FORM:0965301/C1/1> where X is 0 or S and R is an alkyl, alkenyl or dialkylamino-alkyl group or a heterocyclic-substituted acyclic, alkyl-substituted cycloaliphatic or alkoxy-substituted aromatic hydrocarbon iodide, and acid addition and quaternary salts of those compounds which contain a tertiary nitrogen atom in the (thio) ether portion. The ethers are made by treating a -hydroxy-b , b -dimethyl gamma butyrolactone with an amine H2N(CH2)3XR, and are converted into their acid addition salts by treatment with, e.g. mineral acids, or into quaternary compounds by treatment with, e.g. alkyl halides and sulphonates. Specified values of R include methyl, n-decyl, allyl, phytyl, geranyl, diethylaminoethyl, tetrahydrofurfuryl, menthyl and guaiacyl. Preferably X is 0 and R is ethyl. The ethers and their salts are used in pharmaceutical and cosmetic preparations (see Division A5). In examples (1) D(-)-a -hydroxy-b , b -dimethyl-gamma-butyrolactone is treated with 3-methoxypropylamine to form D(+)-a , g -dihydroxy-N-(3-methoxypropyl),b , b -dimethylbutyramide, and in an analogous manner compounds are made in which the propyl radical is substituted in the 3-position with ethyloxy, n-decyloxy, tetrahydrofurfuryloxy, methoxyphenoxy, allyloxy, geranyloxy, phytyloxy, ethylthio, diethylaminoethoxy, L(-)-menthyloxy and dimethylaminoethoxy groups, the last named compound being treated with methyl bromide, in acetone, to yield the bromocholine ether. The propylamines are made by treating appropriate alcohols, or thiols, with acrylonitrile and hydrogenating the cyano group in the addition product. The preparation of 3-methoxy-, 3-allyloxy-, 3-ethylthio-, L(-)-3-menthyloxy- and 3(dimethylaminoethoxy)- propylamines is described in detail.ALSO:Cosmetic and pharmaceutical preparations having Vitamin B5 activity comprise compounds of formula <FORM:0965301/A5-A6/1> where X is O or S and R is an alkyl, alkenyl or dialkylamino-alkyl group or a heterocyclic-substituted acyclic, alkyl-substituted cycloaliphatic or alkoxy-substituted aromatic hydrocarbon radicle, and acid addition and quaternary salts of those compounds that contain a tertiary nitrogen atom in the ether, or thio-ether, portion.  Specified values of R include, methyl, n-decyl, allyl, phytyl, geranyl, diethylaminoethyl, tetrahydrofurfuryl, menthyl and guaicyl.  The pharmaceutical preparations may comprise one, or more, of the compounds in admixture with a pharmaceutical organic, or inorganic, inert carrier material suitable for external, or parenteral, administration, e.g. water, gelatin, lactose, starch, magnesium stearate, talc, vegetable oils, gums, polyalkylene glycols and mineral jelly and be in solid form, e.g. tablets, dragees, suppositories or capsules, or in a liquid form, e.g. solutions, suspensions or emulsions.  They may be sterilized and/or contain e.g. conserving, stabilizing, wetting or emulsifying agents, salts for variation of the osmetic pressure or buffers.  The cosmetic preparations, e.g. hair-washes, hair oils, salves and preparations for skin care, comprise the compounds in solvents, e.g. water, alcohol, diethyl-ether, ethyl acetate, acetone, aqueous alcohols, paraffin oil and fatty substances. Preparations described in examples comprise (A) the compound in which X is O, and R is Et, dissolved in aqueous ethyl or isopropyl alcohol, and colour and perfume, which solution may be diluted with aqueous alcohol, (B) a compound in which X is O, and R is phytyl, dissolved in paraffin oil and which on dilution with more paraffin oil may be used for scalp and hair treatment, (C) a preparation of glycerol monostearate, cetyl alcohol, lanolin, isopropyl myristol, acetostearate, beeswax and (ethoxylated fatty alcohol)/(phosphoric acid ester) together with a compound where X is O and R is Et emulsified with water, (D) as in (C) with the addition of a compound in which X is S and R is Et, (E) a salve, prepared from cetyl alcohol, lanolin white mineral jelly and pantherol ethyl ether, and in (F) a mixture of panthenol ethyl ether, and water, is mixed with polyoxyethylene sorbitol monostearate, and a mixture of hydrogenated peanut oil, and glycerol, added, the whole being emulsified, and allowed to cool, to form a salve-like composition.