Thiolation using

Williams and Rastetter also accomplished an elegant synthesis of ( )-hyalodendrin (83) in 1980 [39]. Beginning with the sarcosine anhydride-derived enolic aldehyde 78, silyl protection of the enal enabled alkylation of the glycine center with benzyl bromide and thiolation using LDA and monoclinic sulfur a la Schmidt. After protection of the thiol with methylsulfenyl chloride and deprotection of the silyl ether, the enol was sulfenylated with triphenylmethyl chlorodisulfide to afford bis(disulfide) 82 as a 2 1 mixture of diastereomers favoring the anti isomer. Reduction of the disulfides with sodium borohydride and oxidation with KI3 in pyridine afforded ( )-hyalodendrin (83) in 29 % yield (Scheme 9.4). 

The following protocol represents a generalized method for protein thiolation using SATA. For comparison purposes, contrast the variation of this SATA modification method as outlined in Chapter 20, Section 1.1 for use in the preparation of antibody-enzyme conjugates. 

Figure 21.12 SIAB can be used to activate toxin molecules for coupling with sulfhydryl-containing antibodies. In this case, the antibody molecule is thiolated using SATA and deprotected to reveal the free sulfhydryl. Reaction with the SIAB-activated toxin forms the final conjugate by thioether bond formation.

The biochemistry and medicinal chemistry of the gold(I) thiolates used in chrysotherapy have been thoroughly reviewed elsewhere9"14,240 and this account will deal only with stability and ligand exchange reactions of the gold(I) thiolates of interest to coordination chemists. 

This procedure is apparently limited to cyanomethylcopper derivatives, copper amides, heteroarylcopper compounds, and copper thiolates. Use of bis(iodomethyl)-zinc, (ICH2)2Zn, results in products from double insertion. 

Figure 6 Structures of the gold(I) monothiolate catanes, [AuSR]io and [AuSR ]i2, R = p-fBu-C6H4S- and R = o-fBu-C6H4S-. The ability to form stable catenated rmg systems may explain the difficulties encountered in preparing crystalline forms of the gold(l) thiolates used clinically. ...

The dithiolate complex [l,5-bis(mercaptoethyl)-l,5-diazacyclooctane]Ni or -Pd reacts with SO2 to produce sulfur-site SO2 adducts and then with O2 to form sulfato complexes. Exogenous thiolates used as an electron source allow SO2 oxygenation to 864 ions [56]. The complex cw-[Pt(SH)2(PPh3)2] catalyzes... 

First, the KE2 antibody is thiolated using iV-succinimidyl-S-acetyl thioacetate in dimethyl strlfoxide. The succinimide group is coupled to the primary amines on the protein (antibody) which leads to the formation of covalent amide bonds with the loss of hydroxy succinimide. The sulfhydryl group is thus protected. The deprotection, through deacetylation, is carried out using EDTA and hydroxyl... 

Reactions involving fracture of P—O or P—N bonds and displacement of EtO and EtgN groups in various 1,3,2-oxaazaphospholanes (40) (R = EtO, EtjN) with thiols in the presence of triethylamine have been examined . Aliphatic thiolates used their sulphur in reaction with 40 to form 50-60% oxaazaphospholane 2-sulphide (41), whereas benzene thiol formed 78% 2-phenylthio-N-phenyl-l,3,2-oxaazaphospholane (42) (R = Ph R = H). Similar derivatives (40 R = R S) are readily prepared from 40 when R = Cl, on treatment with a thiol in the presence of triethylamine . 

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