93748-48-2

Upstream product

• 23985-53-7 (R)-3-hydroxy-2,3-dimethylbutansaeure 
• 73295-12-2 (S)-2,3-dimethyl-1,3-butanediol 
• 104-15-4 toluene-4-sulfonic acid 
• 556-82-1 3-methyl-2-buten-1-ol 
• 71312-15-7 1-benzyloxy-2,3-epoxy-3-methylbutane 
• 62748-09-8 [(2R)-3,3-dimethyloxiran-2-yl]methanol 
• 93748-46-0 (S)-4-Benzyloxy-2,3-dimethyl-butan-2-ol 
• 98-59-9 p-toluenesulfonyl chloride 

Downstream Products

• 112763-33-4 (3R)-2,3-dimethyl-4-(p-tolylsulfonyloxy)but-1-ene 
• 125732-36-7 previtamin D 
• 60133-18-8 ercalcitriol 
• 93748-50-6 (R)-2,3-dimethyl-4-phenylsulfonyl-2-butanol 
• 634611-89-5 Benzoic acid (Z)-(S)-6,7-dimethyl-3-trimethylsilanylmethyl-octa-2,7-dienyl ester 
• 93748-49-3 (R)-2,3-dimethyl-4-phenylthio-2-butanol 
• 21343-40-8 ercalcidiol 
• 93775-08-7 (2S,5R)-4-Benzenesulfonyl-2-[(3S,9S,10R,13R,14R,17R)-10,13-dimethyl-3-(tetrahydro-pyran-2-yloxy)-2,3,4,9,10,11,12,13,14,15,16,17-dodecahydro-1H-cyclopenta[a]phenanthren-17-yl]-5,6-dimethyl-6-(tetrahydro-pyran-2-yloxy)-heptan-3-ol 
• 68702-86-3 Benzoic acid (1R,4S,7aR)-7a-methyl-1-((E)-(1R,4R)-1,4,5-trimethyl-hex-2-enyl)-octahydro-inden-4-yl ester 
• 143317-49-1 R-(+)-4,5,5-Trimethyl-2,2,2-triphenyl-1,2-oxaphospholane 
• 138079-58-0 (R)-2,3-Dimethyl-4-(triphenyl-λ⁵-phosphanylidene)-butan-2-ol 
• 143317-47-9 (E)-(S)-2,3-Dimethyl-5-phenyl-pent-4-en-2-ol 
• 138079-59-1 R-(+)-(2,3-Dimethyl-3-hydroxybutyl)triphenylphosphonium iodide 

Relevant academic research and scientific papers

Preparation method of paricalcitol intermediate

The invention relates to a preparation method of a paricalcitol intermediate, in particular to a preparation method for an intermediate (as shown in a formula (I)) for synthesizing paricalcitol (II). According to the method, a chiral intermediate as shown in a formula (V) through anti-and syn-aldol reaction of a chiral compound as shown in a formula (IV) and acetone, and the intermediate (as shown in a formula (I)) for synthesizing the paricalcitol is obtained through reduction, halogenations and reaction with triphenyl phosphine. The method has the advantages of mild reaction condition, simplicity and convenience in operation, high optical purity, low synthesis cost and the like, and is suitable for large-scale production. (The formulas are as shown in the description.).

A volatile lactone of Hymenoscyphus pseudoalbidus, pathogen of European ash dieback, inhibits host germination

The largely unknown secondary metabolism of the plant pathogenic fungus Hymenoscyphus pseudoalbidus was investigated by use of the CLSA method. A set of volatile lactones was identified by GC/MS. The lactones were synthesized and used in bioassays in which one of the compounds was found to be a strong germination inhibitor for ash seeds, causing necroses in the plant tissue. The largely unknown secondary metabolism of the plant pathogenic fungus Hymenoscyphus pseudoalbidus was investigated by use of the closed-loop stripping apparatus (CLSA) method. A set of volatile lactones was identified by GC/MS. The lactones were synthesized and used in bioassays in which one of the compounds was found to be a strong germination inhibitor for ash seeds.

METHODS FOR PRODUCING PARICALCITOL

The present invention is directed to novel processes for the preparation of paricalcitol to novel intermediates used in these processes, and to processes for preparation of the novel intermediates.

Electrophilic Cyclization of 1,6-Dienes Containing an Allylsilane Moiety - Enantioselective Synthesis of cis- and trans-γ-Irone

In this paper, we report the first examples of Lewis acid and mercuric trifluoroacetate promoted cyclizations of 1,6-dienes containing an allylsilane moiety. Mercuric trifluoroacetate has been proved to be the reagent of choice leading to methylenecyclohexane derivatives in good yields and with complete regioselectivity albeit with poor diastereoselectivity. Using this methodology a stereodivergent synthesis of enantiomerically pure (-)-(2S,6R)-cis-γ -irone and (-)-(2S,6S)-trans-γ-irone, two precious aroma constituents, has been accomplished. This represents an innovative approach with respect to previous syntheses of γ-irones. Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003.

Phosphorus ylide chemistry investigated for dihydrotachysterol2 metabolite side-chain synthesis: The Wittig approach

The behaviour of the γ-oxido ylide of R-(3-hydroxy-2,3-dimethylbutyl)triphenylphosphonium iodide 4, to be used in the 25-hydroxylated DHT2 side-chain synthesis, was studied. The synthesis of the chiral phosponium salt 4 was done in an overall y

A short and efficient synthesis of DE-A,B(22E,24S)-8β-(benzoyloxy)-25-hydroxyergost-22-ene a valuable intermediate in the total synthesis of 25-hydroxylated vitamin D2-metabolites

The titel compound was synthesised in 8 steps starting from vitamin D2. The side-chain was constructed using a chiral, stereoselective Wittig-reagent.

FACILE AND STEREOSELECTIVE SYNTHESIS OF 25-HYDROXYVITAMIN D2

25-Hydroxyvitamin D2 was synthesized conveniently and stereoselectively for the first time by utilizing Sharpless' chiral epoxidation and the subsequent regio- and stereoselective methylation with lithium dimethylcuprate to introduce the desire