Hex Hexyl

HMDS 1,11,3,3,3-Hexamethyldisilazane HMO Huckel molecular orbital HMPA Hexamethylphosphoramide HMPT Hexamethylphosphoroustriamide HOBT 1-Hydroxybenzotriazole

HOMO Highest occupied molecular orbital HPLC High performance liquid chromatography HRMS High-resolution mass spectrum hν Irradiation with light Hz Hertz

hZ Homobenzyloxycarbonyl ICR Ion cyclotron resonance

IDTr 3-(Imidazole-1-ylmethyl)-4’,4”-dimethoxytriphenylmethyl Im Imidazole-1-yl or 1-imidazolyl

iMds 2,6—Dimethoxy-4-methylbenzenesulfonyl INDO Incomplete neglect of differential overlap IP Ionization potential

Ipaoc 1-Isopropylallyloxycarbonyl IPDMS Isopropyldimethylsilyl IR Infrared

J Coupling constant (in NMR) k Kilo

KAPA Potassium 3-aminopropylamide

KHMDS Potassium bis(trimethylsilyl)amide or potassium hexamrthyldisilane L Triphenylphosphine ligand or liter LAH Lithium aluminum hydride

LCAO Linear combination of atomic orbitals LDA Lithium diisopropylamide LDBB 4,4’-Di-tert-butyybiphenyl ylide Lev Levulinoyl

LevS Levulinoyldithioacetal ester 4,4-(ethylenedithio)pentanoyl LFER Linear free energy relationship LICA Lithium isopropylcyclohexylamide

LHMDS Lithium bis(trimethylsilyl)amide or lithium hexamrthyldisilane LTA Lead tetraacetate

LTMP Lithium 2,2,6,6-tetramethylpiperidide LUMO Lowest unoccupied molecular orbital μ Micro

m Multiple (spectral), meter, milli M Moles per liter or mega

MAD Methylaluminum bis(2,6-di-t-butyl-4-methylphenoxide MBE 1-(Methyl-1-benzyloxyethyl

MBF 2,3,3a,4,5,6,7,7a-Octahydro-7,8,8-trimethyl-4,7-methanobenzofuran- 2-yl

MBS p-Methoxybenzenesulfonyl MCPBA m-Chloroperbenzoic acid

Mds 2,6-Dimethyl-4-methoxybenzenesulfonyl m/e Mass to charge ratio (in MS) MEM α-Methoxyethoxymethyl MeOZ p-Methoxybenzyloxycarbonyl Mes Mesityl 2,4,6-trimethylphenyl MHz Megahertz min Minute

MINDO Modified intermediate neglect of differential overlap mM Millimoles per liter

MMTr p-Methoxyphenyldiphenylmethyl MO Molecular orbital mol Mole

MOM Methoxymethyl

MoOPH Oxodiperoxymolybdenum(pyridine) hexamethylphosphoramide Moz p-Methoxybenzyloxycarbonyl mp Melting point

MPM p-Methoxyphenylmethyl or p-Methoxybenzyl Mps p-Methoxyphenylsufonyl Mpt Dimethylthiophosphinyl mRNA Messenger RNA Ms Methanesulfonyl or mesyl MS Mass spectrometry MSA Methanesulfonic acid Msib 4-(Methylsulfinyl)benzyl

Msz 4-Methylsulfinylbenzyloxycarbonyl Mtb 2,4,6-Trimethoxybenzenesufonyl

Mte 2,3,5,6-Tetramethyl-4-methoxybenzenesulfonyl MTHP 4-Methoxytetrahydropyranyl MTM Methylthiomethyl

MTMB 4-(methylthiomethoxy)butyryl

MTMECO 2-(Methylthiomethoxy)ethoxycarbonyl MTMT 2-(Methylthiomethoxymethyl)benzoxy Mtpc 4-Methylthiophenoxycarbonyl

Mtr 2,3,6-Trimethyl-4-methoxybenzenesulfonyl

Mts 2,3,6-Trimethylbenzenesulfonyl(mesitylenesulfonyl)

m/z Mass to charge ratio (in MS) n nao

NAD Nicotinamide adenine dinucleotide NADH Reduced NAD NBA N-Bromoacetamide NBS N-Bromosuccinimide NCS N-Chlorosuccinimide Ni(acac)2 Nickel acetylacetonate NIS N-Iodosuccinimide Ni(R) Raney Nickel NMM N-Methyl morpholine NMR Nuclear magnetic resonance Noc 4-Nitrocinnamyloxycarbonyl NOE Nuclear Overhauser effect

NOESY Nuclear Overhauser effect spectroscopy NPS 2-Nitrophenylsulfenyl Npys 3-Nitro-2-pyridinesulfenyl Nu Nucleophile OD Optical density ONB o-Nitrobenzyl

ORD Optical rotary dispersion ot Oven temperature

PADA Potassium azodicarboxylate PCC Pyridinium chlorochromate PDC Pyridinium dichromate

PdCl2(tpp)2 Dichlorobis[tris(2-methylphenyl)phosphine]palladium Pd2(dba)3 Tris(dibenzylideneacetone)dipalladium PE Photoelectron

Peoc 2-Phosphonioethoxycarbonyl or 2-(Triphenylphosphonio)ethoxycarbonyl C. Chen, NDNU, 2003/06/13 Pet 2-(2’-Pyridyl)ethyl PG Protective group Ph Phenyl φ Phenyl

Phen 1,10-Phenanthroline

Phenoc 4-Methoxyphenacyloxycarbonyl Phth Phthaloyl

Pixyl 9-(9-Phenyl)xanthenyl PMB p-Methoxybenzyl

PMBM p-Methoxybenzoxymethyl

Pmc 2,2,5,7,8-Pentamethylchroman-6-sulfonyl Pme Pentamethylbenzenesulfonyl PMS p-Methylbenzylsulfonyl PNB p-Nitrobenzoyl

PNBSP p-Nitrobenzenesulfonyl peroxide POM 4-Pentenyloxymethyl or Pivaloxymethyl PPA Polyphosphoric acid PPE Polyphosphate ester ppm Parts per mollion

Ppoc 2-Triphenylphosphonioisopropoxycarbonyl PPTS Pyridinium p-to;uenesulfonate Pr Propyl i-Pr Isopropyl

Psec 2-(Phenylsulfonyl)ethoxycarbonyl PTM Phenylthiomethyl PTC Phase-transfer catalysis Pv Pivaloyl Py Pyridine

Pyoc 2-(2’- and 4’-pyridyl)ethoxycarbonyl q Quartet

Rf Retention factor rRNA Ribosomal RNA rt Room temperature s Singlet or second

Scm S-Carboxymethylsulfenyl

ScmCl Methoxycarbonylsulfenyl chloride SEM Trimethylsilylmeyhoxyethyl SES β-Trimethylsilylethanesulfonyl SET Single electron transfer

SMOM (Phenyldimethylsilyl)methoxymethyl SN1 Unimolecular nucleophilic substitution SN2 Bimolecular nucleophilic substitution

SN’ Nucleophilic substitution with allylic rearrangement Snm S-(N’-Methyl-N’-phenylcarbamoyl)sulfenyl STABASE 1,1,4,4-Tetramethyldisilyl azacyclopentane Su Succinimidyl t Triplet

Tacm Trimethylacetamidomethyl TBAF Tetrabutylammonium fluoride TBAI Tetrabutylammonium iodide TBDMS t-Butyldimethylsilyl