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With roots in ancient formulations, methods for the chemical derivatization of proteins continue to expand and develop. The creation of this new journal dealing exclusively with bioconjugate chemistry was barely conceivable just a few years ago. An explosion of interest in the subject during the last decade is, however, easily seen. The tremendous growth in both the number of publications and in the number of research groups involved in these kinds of studies has been promoted by both practical interests related, for example, in some cases to possible pharmacological or medical diagnostic applications and by interest in questions of fundamental biochemical structure and function.Greatly Reagents have been designed to preserve electrostatic charge (4,5), to alter electrostatic charge (6), and to increase hydrophobicity (7,8). Reagents and procedures have been developed to decrease immunogenicity (9, 20), to increase and decrease susceptibility to proteolysis (22-23), to increase UV or visible absorbancy (14), to introduce fluorescent labels (25,16), spin labels (27), radiolabels , various metal ions (22), magnetic microspheres (22,23), and electron-dense substituents (24), to increase the content of certain low-abundance nonradioactive isotopes (25)

Human serum albumin reacts very rapidly with p-nitrophenyl acetate (NphOAc). Rapid acetylation of the protein accompanies and largely accounts for the easily observed rapid formation of of p-nitrophenolate ion. One group is acetylated much faster than all others. It appears to be located in a high affinity binding site for small fatty acid anions, to have a pKa of 8.7, and a limiting bimolecular rate of reaction with NphOAc of approximately 3 X 10(4) M-1 sec-1 at alkaline pH values. Rapid reversible binding appears to be a major contributor to the high reaction velocity.

pyrene ll-bromo-9,10,12-triol, minor isomer, 70981-82-7; 10,11-epoxy-9,12-dihydroxy-9,10,11,12-tetrahydrobenzo[e]pyrene, 70940-93-1; 10,11-epoxy-9,12-dihydroxy-9,10,11,12-tetrahydrobenzo[e]pyrene diacetate, 70982-62-6; trans-1 triphenylene tetra01 tetraacetate, 70940-94-2; trans-% triphenylene tetraol tetraacetnte, 70981-83-8; cis-2 triphenylene tetraol tetraacetate, 70981-84-9; trar s-l benio [e]pyrene tetraol tetraacetate, 70940-95-3; cis-1 benzo[e]p~rene tetraol tetraacetate, 70981-85-0; trans-2 benzo[e]pyrene tetraol tetraacetate, 70981-86-1; cis-2 benzo[e]pyrene tetraol tetraacetate, 70981-87-2 Supplementary Material Available: Details on the hydrolysis of the Senzo[ejpyrene and triphenylene diol epoxides to tetraols and their 'H NMR spectra as tetraacetates, and the reaction of b~nzo[e]pyrene 9,lO-dihydrodiol with N-bromoacetamide as well as the cyclization of the resultant bromo triols (4 pages). Ordering information is given on any current masthead page. ~~ (16) A.Summary: a$-Acetylenic sulfones react with organolithium and Grignard reagents to give a higher acetylene and a sulfinate salt. The process corresponds to nucleophilic substitution by the organometallic for the arylsulfonyl group.

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